Variable frequency drive configuration for electric driven hydraulic fracking system

ABSTRACT

An electric driven hydraulic fracking system is disclosed. A pump configuration that includes the single VFD, the single shaft electric motor, and the single hydraulic pump that is mounted on the single pump trailer. A pump configuration includes a single VFD configuration, the single shaft electric motor, and the single shaft hydraulic pump mounted on the single pump trailer. The single VFD configuration converts the electric power at the power generation voltage level distributed from the power distribution trailer to a VFD voltage level and drives the single shaft electric motor to control the operation of the single shaft electric motor and the single hydraulic pump. The VFD voltage level is a voltage level that is required to drive the single shaft electric motor. The VFD configuration also controls operation of the auxiliary systems based on the electric power at the auxiliary voltage level.

FIELD OF DISCLOSURE

This application is a U.S. Nonprovisional Application which claims thebenefit of U.S. Provisional Application No. 62/805,521 filed on Feb. 14,2019, which is incorporated herein by reference in its entirety. Thisapplication also incorporates U.S. Nonprovisional application Ser. No.16/790,392 herein by reference in its entirety. This application alsoincorporates U.S. Nonprovisional application Ser. No. 16/790,538.

BACKGROUND Field of Disclosure

The present disclosure generally relates to electric driven hydraulicfracking systems and specifically to a single Variable Frequency Drive(VFD), a single shaft electric motor, and a single hydraulic pumppositioned on a single pump trailer.

Related Art

Conventional hydraulic fracking systems are diesel powered in thatseveral different diesel engines apply the power to the hydraulic pumpsas well as several types of auxiliary systems that assist the hydraulicpumps to execute the fracking, such as hydraulic coolers and lube pumps.Conventional diesel powered hydraulic fracking systems require a dieselengine and a transmission to be connected to a hydraulic pump to drivethe hydraulic pump. However, typically several hydraulic pumps arerequired at a single fracking site to prepare the well for the laterextraction of the fluid, such as hydrocarbons, from the existing well.Thus, each of the several hydraulic pumps positioned at a singlefracking site require a single diesel engine and single transmission toadequately drive the corresponding hydraulic pump requiring severaldiesel engines and transmissions to also be positioned at the singlefracking site in addition to the several hydraulic pumps.

Typically, the diesel engines limit the horsepower (HP) that thehydraulic pumps may operate thereby requiring an increased quantity ofhydraulic pumps to attain the required HP necessary prepare the well forthe later extraction of fluid, such as hydrocarbons, from the existingwell. Any increase in the power rating of hydraulic pumps also resultsin an increase in the power rating of diesel engines and transmissionsrequired at the fracking site as each hydraulic pump requires asufficiently rated diesel engine and transmission. As the dieselengines, transmissions, and hydraulic pumps for a single fracking siteincrease, so does quantity of trailers required to transport andposition configurations at the fracking site.

The numerous diesel engines, transmissions, and hydraulic pumps requiredat a fracking site significantly drives up the cost of the frackingoperation. Each of the numerous trailers required to transport andposition configurations require CDL drivers to operate as well asincreased manpower to rig the increased assets positioned at thefracking site and may be classified as loads in need of permits, thusadding expense and possible delays. The amount of diesel fuel requiredto power the numerous diesel engines to drive the numerous hydraulicpumps required to prepare the well for the later extraction of thefluid, such as hydrocarbons, from the existing well also significantlydrives up the cost of the fracking operation. Further, the parasiticlosses typically occur as the diesel engines drive the hydraulic pumpsas well as drive the auxiliary systems. Such parasitic losses actuallydecrease the amount of HP that is available for the hydraulic pumpsoperate thereby significantly decreasing the productivity of hydraulicpumps. In doing so, the duration of the fracking operation is extendedresulting in significant increases in the cost of the frackingoperation. The diesel engines also significantly increase the noiselevels of the fracking operation and may have difficulty operatingwithin required air quality limits.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

Embodiments of the present disclosure are described with reference tothe accompanying drawings. In the drawings, like reference numeralsindicate identical or functionally similar elements. Additionally, theleft most digit(s) of a reference number typically identifies thedrawing in which the reference number first appears.

FIG. 1 illustrates a top-elevational view of a hydraulic frackingoperation such that the hydraulic pumps may pump a fracking mixture intoa fracking well to execute a fracking operation to extract a fluid fromthe fracking well;

FIG. 2 illustrates a top-elevational view of a single pump configurationthat includes a single VFD, a single shaft electric motor, and a singlehydraulic pump that are each mounted on a single pump trailer;

FIG. 3 illustrates a block diagram of an electric driven hydraulicfracking system that provides an electric driven system to execute afracking operation in that the electric power is consolidated in a powergeneration system and then distributed such that each component in theelectric driven hydraulic fracking system is electrically powered;

FIG. 4 illustrates a top-elevational view of a mobile substation forelectric power provided by the electric utility grid as the powergeneration system;

FIG. 5 illustrates a block diagram of an electric driven hydraulicfracking system that provides an electric driven system to execute afracking operation in that a VFD configuration includes a plurality ofVFD cells that are isolated in order to generate the electric power atthe VFD voltage level to drive the single shaft motor; and

FIG. 6 illustrates a block diagram of an electric driven hydraulicfracking system that provides an electric driven system to execute afracking operation in that a VFD configuration includes a plurality ofVFD cells that are electrically connected to a corresponding VFDcontactor from a plurality of VFD contactors in order to bypass a VFDcell that is no longer operating at its full capacity such that thefracking operation continues.

DETAILED DESCRIPTION OF THE PRESENT DISCLOSURE

The following Detailed Description refers to accompanying drawings toillustrate exemplary embodiments consistent with the present disclosure.References in the Detailed Description to “one exemplary embodiment,” an“exemplary embodiment,” an “example exemplary embodiment,” etc.,indicate the exemplary embodiment described may include a particularfeature, structure, or characteristic, but every exemplary embodimentmay not necessarily include the particular feature, structure, orcharacteristic. Moreover, such phrases are not necessarily referring tothe same exemplary embodiment. Further, when a particular feature,structure, or characteristic may be described in connection with anexemplary embodiment, it is within the knowledge of those skilled in theart(s) to effect such feature, structure, or characteristic inconnection with other exemplary embodiments whether or not explicitlydescribed.

The exemplary embodiments described herein are provided for illustrativepurposes, and are not limiting. Other exemplary embodiments arepossible, and modifications may be made to the exemplary embodimentswithin the spirit and scope of the present disclosure. Therefore, theDetailed Description is not meant to limit the present disclosure.Rather, the scope of the present disclosure is defined only inaccordance with the following claims and their equivalents.

Embodiments of the present disclosure may be implemented in hardware,firmware, software, or any combination thereof. Embodiments of thepresent disclosure may also be implemented as instructions applied by amachine-readable medium, which may be read and executed by one or moreprocessors. A machine-readable medium may include any mechanism forstoring or transmitting information in a form readable by a machine(e.g., a computing device). For example, a machine-readable medium mayinclude read only memory (“ROM”), random access memory (“RAM”), magneticdisk storage media, optical storage media, flash memory devices,electrical optical, acoustical or other forms of propagated signals(e.g., carrier waves, infrared signals, digital signals, etc.), andothers. Further firmware, software routines, and instructions may bedescribed herein as performing certain actions. However, it should beappreciated that such descriptions are merely for convenience and thatsuch actions in fact result from computing devices, processors,controllers, or other devices executing the firmware, software,routines, instructions, etc.

For purposes of this discussion, each of the various componentsdiscussed may be considered a module, and the term “module” shall beunderstood to include at least one software, firmware, and hardware(such as one or more circuit, microchip, or device, or any combinationthereof), and any combination thereof. In addition, it will beunderstood that each module may include one, or more than one, componentwithin an actual device, and each component that forms a part of thedescribed module may function either cooperatively or independently fromany other component forming a part of the module. Conversely, multiplemodules described herein may represent a single component within anactual device. Further, components within a module may be in a singledevice or distributed among multiple devices in a wired or wirelessmanner.

The following Detailed Description of the exemplary embodiments will sofully reveal the general nature of the present disclosure that otherscan, by applying knowledge of those skilled in the relevant art(s),readily modify and/or adapt for various applications such exemplaryembodiments, without undue experimentation, without departing from thespirit and scope of the present disclosure. Therefore, such adaptationsand modifications are intended to be within the meaning and plurality ofequivalents of the exemplary embodiments based upon the teaching andguidance presented herein. It is to be understood that the phraseologyor terminology herein for the purpose of description and not oflimitation, such that the terminology or phraseology of the presentspecification is to be interpreted by those skilled in the relevantart(s) in light of the teachings herein.

System Overview

FIG. 1 illustrates a top-elevational view of a hydraulic frackingoperation such that the hydraulic pumps may pump a fracking media into awell to execute a fracking operation to extract a fluid from the well. Ahydraulic fracking operation 100 includes a fracking trailer 170 that afracking configuration may be deployed. The fracking configuration maybe the fracking equipment that executes the actual fracking to preparethe well for the later extraction of the fluid from the well. Forexample, the fracking trailer 170 may include the fracking equipmentthat implements the missile as well as the well heads that are affixedonto the well and distribute the fracking media into the well to preparethe well for later extraction of the fluid from the well. The fluidextracted from the well may include a liquid, such as crude oil, and soon, or a gas, such as such as hydrocarbons, natural gas and so on, thatis extracted from the well that is then stored and distributed.

The power that is generated to provide power to each of the numerouscomponents included in the hydraulic fracking operation 100 ispositioned on a power generation system 110. Often times, the frackingsite is a remote site where it has been determined that sufficient fluidhas been located underground to justify temporarily establishing thehydraulic fracking operation 100 for a period of time to drill the welland extract the fluid from the well. Such fracking sites are often timespositioned in remote locations such as uninhabited areas in mountainousregions with limited road access to the fracking sites such that thehydraulic fracking operation 100 is often times a mobile operation whereeach of the components are positioned on trailers that are then hauledto the fracking site via semi-trucks and/or tractors. For example, thefracking trailer 170 includes the fracking equipment which is hauled invia a semi-truck and is positioned closest to the well as compared tothe other components in order to execute the fracking operation.

In another example, the power generation system 110 may also be a mobileoperation such that the power generation equipment may be mounted on apower generation trailer and transported to the fracking site via asemi-truck and/or tractor. The power generation system 110 may bepositioned on the fracking site such that any component of the hydraulicfracking operation 100 may be powered by the power generation system110. In doing so, the power required for the hydraulic frackingoperation 100 may be consolidated to the power generation system 110such that the power generation system 110 provides the necessary powerrequired for the hydraulic fracking operation 100. Thus, the powergeneration system 110 may be positioned at the fracking site in a mannersuch that each component of the hydraulic fracking operation 100 mayhave power distributed from the power generation system 110 to eachrespective component of the hydraulic fracking operation 100.

The power generation system 110 may include power generation systemsthat generate electric power such that the hydraulic fracking operation100 is powered via electric power generated by the power generationsystem 110 and does not require subsidiary power generation systems suchas subsidiary power generation systems that include diesel engines. Indoing so, the power generation system 110 may provide electric power toeach component of the hydraulic fracking operation 100 such that thehydraulic fracking operation 100 is solely powered by electric powergenerated by the power generation system 110. The power generationsystem 110 may consolidate the electric power that is generated for theelectric driven hydraulic fracking system 100 such that the quantity andsize of power sources included in the power generation system 110 isdecreased.

The power sources are included in the power generation system 110 andoutput electric power such that the electric power outputted from eachpower source included in the power generation system 110 is collectivelyaccumulated to be electric power at a power generation voltage level aswill be discussed in detail below. For example, the power output foreach of the power sources included in the power generation system 110may be paralleled to generate the electric power at the power generationvoltage level. The power generation system 110 may include numerouspower sources as well as different power sources and any combinationthereof. For example, the power generation system may include powersources that include a quantity of gas turbine engines. In anotherexample, the power generation system 110 may include a power source thatincludes an electric power plant that independently generates electricpower for an electric utility grid. In another example, the powergeneration system 110 may include a combination of gas turbine enginesand an electric power plant. The power generation system 110 maygenerate the electric power at a power level and a voltage level.

The power generation system 110 may generate electric power at a powergeneration voltage level in which the power generation voltage level isthe voltage level that the power generation system is capable ofgenerating the electric power. For example, the power generation system110 when the power sources of the power generation system 110 include aquantity of gas turbine engines may generate the electric power at thepower generation voltage level of 13.8 kV which is a typical voltagelevel for electric power generated by gas turbine engines. In anotherexample, the power generation system 110 when the power sources of thepower generation system include an electric power plan may generate theelectric power at the power generation voltage level of 12.47 kV whichis a typical voltage level for electric power generated by an electricpower plant.

In another example, the power generation system 110 may generateelectric power that is already at a VFD voltage level to power thesingle shaft electric motor 150(a-n) as discussed in detail below. Insuch an example, the power generation system 110 may generate theelectric power that is already at the VFD voltage level of 4160V. Inanother example, the power generation system 110 may generate theelectric power at the power generation voltage level at a range of 4160Vto 15 kV. In another example, the power generation system 110 maygenerate electric power at the power generation voltage level of up to38 kV. The power generation system 110 may generate the electric powerat any power generation voltage level that is provided by the powersources included in the power generation system 110 that will beapparent to those skilled in the relevant art(s) without departing fromthe spirit and scope of the disclosure. The power generation system 110may then provide the electric power at the power generation voltagelevel to the power distribution trailer 120 via a medium voltage cable.

In an embodiment, the power generation system 110 may generate electricpower at a power level of at least 24 Mega Watts (MW) that is generatedat a power generation voltage level of at least 13.8 kV. In anotherembodiment, the power generation system 110 may generate electric powerat a power level of at least 24 MW that is generated at a powergeneration voltage level of at least 12.47 kW. The power generationsystem 110 may generate electric power at a power level such that thereis sufficient electric power to adequately power each of the componentsof the hydraulic fracking operation 100 while having gas turbine enginesin quantity and in size that enable the gas turbine engines to betransported to the fracking site and set up remotely via a trailer. Indoing so, the power distribution trailer 110 may include gas turbineengines that generate sufficient electric power to adequately power eachof the components of the hydraulic fracking operation 100 while notrequiring a large quantity of gas turbine engines and gas turbineengines of significant size that may significantly increase thedifficulty and the cost to transport the gas turbine engines to thefracking site.

In order to provide sufficient electric power to adequately power eachof the components of the hydraulic fracking operation 100 while notrequiring large quantities of gas turbine engines and/or gas turbineengines of significant size, the power distribution trailer 110 mayinclude single or multiple gas turbine engines that generate electricpower at power levels of 5 MW, 12 MW, 16 MW, 20-25 MW, 30 MW and/or anyother wattage level that may not require large quantities of gas turbineengines and/or gas turbine engines of significant size that will beapparent to those skilled in the relevant art(s) without departing fromthe spirit and scope of the disclosure. In another example, the powergeneration system 110 may be the electric utility power plant that islocal to the location of the fracking operation such that the powerdistribution trailer 120 may receive the electric power at the powerlevel of 24 MW and the power generation voltage level of 12.47 kVdirectly from the electric utility power plant.

In an embodiment, the power generation system 110 may include a firstgas turbine engine that generates electric power at a first power levelin range of 12 MW to 16 MW and a second gas turbine engine thatgenerates electric power at a second power level in a range of 12 MW to16 MW. The first gas turbine engine and the second gas turbine enginegenerate the same voltage level of at least 13.8 kV that is provided toa power distribution trailer 120 when the first power level is in therange of 12 MW to 16 MW generated by the first gas turbine engine iscombined with the second power level in the range of 12 MW to 16 MW. Inorder to provide sufficient electric power to adequately power eachcomponent of the hydraulic fracking operation 100 as well as limit thequantity of gas turbine engines as well as the size of the gas turbineengines such that the gas turbine engines may be positioned on a singletrailer and transported to the fracking site, the power generationsystem 110 may include two electric gas turbine engines that generateelectric power at power levels in the range of 12 MW to 16 MW such thatthe electric powers at the power levels in the range of 12 MW to 16 MWmay be paralleled together to generate the total electric power that isavailable to power each of the components of the hydraulic frackingoperation 100 is in the range of 24 MW to 32 MW.

Further, the power generation system 110 including more than one gasturbine engine to generate the electric power provides redundancy in thepower generation for the hydraulic fracking operation 100. In doing so,the power generation system 110 provides a redundancy to the electricdriven hydraulic fracking system in that the first gas turbine enginecontinues to provide the first power level to the power distributiontrailer 120 when the second gas turbine engine suffers a short circuitand/or other shutdown condition and the second gas turbine enginecontinues to provide the second power level to the power distributiontrailer 120 when the first gas turbine engine suffers the short circuitand/or other shutdown condition. The power generation system 110 maythen maintain a reduced quantity of hydraulic pump(s) 160(a-n) tocontinuously operate in the continuous duty cycle without interruptionin continuously pumping the fracking media due to the redundancyprovided by the first gas turbine engine and the second gas turbineengine.

By incorporating two gas turbine engines that generate electric power atpower levels in the range of 12 MW to 16 MW redundancy may be providedin that the electric power that is provided to the components of thehydraulic fracking operation 100 such that the fracking media iscontinuously pumped into the well to execute the fracking operation toprepare the well for the later extraction of the fluid from the welldespite one of the gas turbine engines suffering a short circuitcondition. In doing so, the incident energy at the point where the shortcircuit occurs may be reduced due to the reduced short circuitavailability of the power generation system 110. However, if one of thegas turbine engines were to fail due to a short circuit condition, theremaining gas turbine engine may continue to provide sufficient power toensure the fracking media is continuously pumped into the well. Afailure to continuously pump the fracking media into the well may resultin the sand, which is a major component of the fracking media coming outof the suspension and creating a plug at the bottom of the well whichtypically results in a significant expense to remove the sand in thewell so that the fracking can continue. The power generation system 110may include any combination of gas turbine engines and/or single gasturbine engine at any power level to sufficiently generate electricpower to adequately power each of the components of the hydraulicfracking operation 100 that will be apparent to those skilled in therelevant art(s) without departing from the spirit and scope of thedisclosure.

The power generation system 110 may generate the electric power at apower generation voltage level that is in the medium voltage range of1.0 kilo Volts (kV) to 72.0 kV. However, in an embodiment, the powergeneration system 110 may generate the electric power at the powergeneration voltage level of 13.8 kV. In another embodiment, the powergeneration system 110 may generate the electric power at the powergeneration voltage level of 13.8 kV. The generation of the electricpower at the voltage level in the medium voltage range enables mediumvoltage cables to be used to connect the power generation system 110 tothe power distribution trailer 120 to propagate the electric power fromthe power generation system 110 to the power distribution trailer 120 aswell as enabling the use of medium voltage cables to propagate theelectric voltage level to any of the components powered by the electricpower in the medium voltage range. The use of medium voltage cablesrather than the use of low voltage cables decreases the size of thecable required in that medium voltage cables require less copper thanlow voltage cables thereby reducing the size and/or quantity of thecables required for the distribution of power throughout the hydraulicfracking operation 100.

Further, the consolidation of gas turbine engines to decrease thequantity of gas turbine engines required to power the components of thehydraulic fracking operation 100 and/or the incorporation of theelectric utility power plant also consolidates the quantity of mediumvoltage cables that are required to connect each of the gas turbineengines to the power distribution trailer 120 thereby further reducingthe cost of the cables required for the hydraulic fracking operation100. Further, the power generation system 110 generated the electricpower at the power generation voltage level of 13.8 kV and/or 12.47 kVenables the hydraulic fracking operation 100 to be more easilyintegrated with any electric utility grid anywhere in the world suchthat the electric utility grid may be more easily substituted into thepower generation system 110 in replacement of the gas turbine enginessince it is more common that the electric utility grid has transformersavailable to deliver the electric power at the power generation voltagelevel of 13.8 kV and/or 12.47 kV.

The power distribution trailer 120 may distribute the electric power atthe power level generated by the power generation system 110 to eachvariable frequency drive (VFD) 140(a-n) positioned on each pump trailer130(a-n). As noted above, the power generation system 110 may include atleast one gas turbine engine, the electric utility grid, and/or acombination thereof, to generate the electric power. In doing so, amedium voltage power cable may be connected from each component of thepower generation system 110 to the power distribution trailer 120. Forexample, the power generation system 110 may include two gas turbineengines with each of the gas turbine engines generating electric powerat the power level of 12 MW to 16 MW at the voltage level of 13.8 kV. Insuch an example, two medium voltage cables may then connect each of thetwo gas turbine engines to the power distribution trailer 120 such thatthe electric power at the power level of 12 MW to 16 MW at the voltagelevel of 13.8 kV may propagate from the gas turbine engines to the powerdistribution trailer 120.

The power distribution trailer 120 may then distribute the electricpower to each of the VFDs 140(a-n) positioned on each of the pumptrailers 130(a-n). As will be discussed in detail below, severaldifferent hydraulic pumps 160(a-n) may be required to continuously pumpthe fracking media into the well to execute the fracking operation toprepare the well for the later extraction of the fluid from the well. Indoing so, each of the different hydraulic pumps 160(a-n) may be drivenby a corresponding VFD 140(a-n) also positioned on the correspondingpump trailer 130(a-n) with the hydraulic pump 160(a-n). Each of the VFDs140(a-n) may then provide the appropriate power to drive each of thesingle shaft electric motors 150(a-n) that then drive each of thehydraulic pumps 160(a-n) to continuously pump the fracking media intothe well to execute the fracking operation to prepare the well for thelater extraction of the fluid from the well. Thus, the powerdistribution trailer 120 may distribute the electric power generated bythe power distribution trailer 110 which is consolidated to reduce thequantity of the gas turbine engines to the several different VFDs140(a-n) positioned on each of the pump trailers 130(a-n). Thecomponents of the power distribution trailer 120 may be transported tothe fracking site.

For example, the power distribution trailer 120 is configured todistribute the electric power at the power level of at least 24 MWgenerated by the at least one gas turbine engine from the voltage levelof at least 13.8 kV to the single VFD 140 a positioned on the singlepump trailer 130 a. In such an example, the power generation system 110includes two different gas turbine engines that generate the electricpower at the power level of 12 MW to 16 MW and at the voltage level of13.8 kV. Two different medium voltage cables may then propagate theelectric power generated by each of the two gas turbine engines at thepower level of 12 MW to 16 MW and at the voltage level of 13.8 kV to thepower distribution trailer 120. The power distribution trailer 120 maythen combine the power levels of 12 MW to 16 MW generated by each of thetwo gas turbine engines to generate a power level of 24 MW to 32 MW atthe voltage level of 13.8 kV. The power distribution trailer 120 maythen distribute the electric power at the voltage level of 13.8 kV toeach of eight different VFDs 140(a-n) via eight different medium voltagecables that propagate the electric power at the voltage level of 13.8 kVfrom the power distribution trailer 120 to each of the eight differentVFDs 140(a-n). The power distribution trailer 120 may distribute thepower generated by any quantity of gas turbine engines to any quantityof VFDs that will be apparent to those skilled in the relevant art(s)without departing from the spirit and scope of the disclosure.

In an embodiment, the power distribution trailer 120 may include aplurality of switch gear modules in that each switch gear moduleswitches the electric power generated by each of the components of thepower generation system 110 and received by the corresponding mediumvoltage cable to the medium voltage cable on and off to each of thecorresponding VFDs 140(a-n). For example, the power distribution trailer120 may include eight different switch gear modules to independentlyswitch the electric power generated by the two gas turbine engines atthe medium voltage level of 13.8 kV as received by the two differentmedium voltage cables on and off to the eight different medium voltagecables for each of the eight corresponding VFDs 140(a-n) to distributethe electric power at the medium voltage level of 13.8 kV to each of theeight corresponding VFDs 140(a-n).

In such an embodiment, the switch gear modules may include a solid stateinsulated switch gear (2SIS) that is manufactured by ABB and/orSchneider Electric. Such medium voltage switch gears may be sealedand/or shielded such that there is no exposure to live medium voltagecomponents. Often times the fracking site generates an immense amount ofdust and debris so removing any environmental exposure to live mediumvoltage components as provided by the 2SIS gear may decrease themaintenance required for the 2SIS. Further, the 2SIS may be permanentlyset to distribute the electric power from each of the gas turbineengines to each of the different VFDs 140(a-n) with little maintenance.The power distribution trailer 120 may incorporate any type of switchgear and/or switch gear configuration to adequately distribute theelectric power from the power generation system 110 to each of thedifferent VFDs 140(a-n) that will be apparent to those skilled in therelevant art(s) without departing from the spirit and scope of thedisclosure.

As noted above, the power distribution trailer 120 may distribute theelectric power at the power generation voltage level generated by thepower generation system 110 to each of the different VFDs 140(a-n)positioned on the corresponding pump trailer 130(a-n). FIG. 2illustrates a top-elevational view of a single pump configuration 200that includes a single VFD 240, a single shaft electric motor 250 and asingle hydraulic pump 260 that are each mounted on a single pump trailer230. The single pump configuration 200 shares many similar features witheach pump trailer 130(a-n) that includes each corresponding VFD140(a-n), single shaft electric motor 150(a-n), and single hydraulicpump 160(a-n) depicted in the hydraulic fracking operation 100;therefore, only the differences between the single pump configuration200 and the hydraulic fracking operation 100 are to be discussed infurther details.

The power distribution trailer 120 may distribute the electric power atthe voltage level generated by the power generation system 110 to thesingle VFD 240 that is positioned on the single pump trailer 130(a-n).The single VFD 240 may then drive the single shaft electric motor 250and the single hydraulic pump 260 as well as control the operation ofthe single shaft electric motor 250 and the single hydraulic pump 260 asthe single shaft electric motor 250 continuously drives the singlehydraulic pump 260 as the single hydraulic pump 260 continuously pumpsthe fracking media into the well to execute the fracking operation toprepare the well for the later extraction of the fluid from the well. Indoing so, the VFD 240 may convert the electric power distributed by thepower distribution trailer 120 at the power generation voltage levelgenerated by the power generation system 110 to a VFD voltage level thatis a voltage level that is adequate to drive the single shaft electricmotor 250. Often times, the power generation voltage level of theelectric power distributed by the power distribution trailer 120 asgenerated by the power generation system 110 may be at a voltage levelthat is significantly higher than a voltage level that is adequate todrive the single shaft electric motor 250. Thus, the single VFD 240 mayconvert the power generation voltage level of the electric power asdistributed by the power distribution trailer 120 to significantly lower(or higher) the voltage level to the VFD voltage level that is needed todrive the single shaft electric motor 250. In an embodiment, the singleVFD 240 may convert the power generation voltage level of the electricpower as distributed by the power distribution trailer 120 to the VFDvoltage level of at least 4160V. In another embodiment, the single VFD240 may convert the power generation voltage level of the electric poweras distributed by the power distribution trailer 120 to the VFD voltagelevel that ranges from 4160V to 6600V. In another embodiment, the singleVFD 240 may convert the power generation level of the electric power asdistributed by the power distribution trailer 120 to the VFD voltagelevel that ranges from 0V to 4160V.

For example, the power generation system 110 generates the electricpower at a power generation voltage level of 13.8 kV. The powerdistribution trailer 120 then distributes the electric power at thepower generation voltage level of 13.8 kV to the single VFD 240.However, the single shaft electric motor 250 operates at a rated voltagelevel of at least 4160V in order to drive the single hydraulic pump 260in which the rated voltage level of at least 4160V for the single shaftelectric motor 250 to operate is significantly less than the powergeneration voltage level of 13.8 kV of the electric power that isdistributed by the power distribution trailer 120 to the single VFD 240.The single VFD 240 may then convert the electric power at the powergeneration voltage level of at least 13.8 kV distributed from the powerdistribution trailer 120 to a VFD rated voltage level of at least 4160Vand drive the single shaft electric motor 250 that is positioned on thesingle pump trailer 230 at the VFD rated voltage level of at least 4160Vto control the operation of the single shaft electric motor 250 and thesingle hydraulic pump 260. The single VFD 240 may convert any voltagelevel of the electric power distributed by the power distributiontrailer 120 to any VFD voltage level that is adequate to drive thesingle shaft electric motor that will be apparent to those skilled inthe relevant art(s) without departing from the spirit and scope of thedisclosure.

The single VFD 240 may also control the operation of the single shaftelectric motor 250 and the single hydraulic pump 260. The single VFD 240may include a sophisticated control system that may control in real-timethe operation of the single shaft electric motor 250 and the singlehydraulic pump 260 in order for the single shaft electric motor 250 andthe single hydraulic pump 260 to adequately operate to continuously pumpthe fracking media into the well to execute the fracking operation toprepare the well for the later extraction of the fluid from the well.Although, the single shaft electric motor 250 and the single hydraulicpump 260 may operate continuously to continuously pump the frackingmedia into the well, such continuous operation may not be continuouslyexecuted with the same parameters throughout the continuous operation.The parameters in which the single shaft electric motor 250 and thesingle hydraulic pump 260 may continuously operate may actually varybased on the current state of the fracking operation. The single VFD 240may automatically adjust the parameters in which the single shaftelectric motor 250 and the single hydraulic pump continuously operate toadequately respond to the current state of the fracking operation.

As noted above, the single VFD 240 may convert the electric power at thepower generation voltage level distributed by the power distributiontrailer 120 to the VFD voltage level that is adequate to drive thesingle shaft electric motor 250. The single shaft electric motor 250 maybe a single shaft electric motor in that the single shaft of theelectric motor is coupled to the single hydraulic pump 260 such that thesingle shaft electric motor 250 drives a single hydraulic pump in thesingle hydraulic pump 260. The single shaft electric motor 250 maycontinuously drive the single hydraulic pump 260 at an operatingfrequency to enable the single hydraulic pump 260 to continuously pumpthe fracking media into the well to execute the fracking operation toprepare the well for the later extraction of the fluid from the well.The single shaft electric motor 250 may operate at the VFD voltagelevels and at the operating frequencies below or above the rated levelsin order to rotate at a RPM level that is appropriate to continuouslydrive the single hydraulic pump 260 at the maximum horsepower (HP) levelthat the single hydraulic pump 260 is rated to pump. In an embodiment,the single shaft electric motor 250 may operate at a VFD voltage levelof at least 4160V. In an embodiment, the single shaft electric motor 250may operate at a VFD voltage level in a range of 4160V to 6600V. In anembodiment, the single shaft electric motor 250 may operate at a VFDvoltage level in arrange of 0V to 4160V. The single shaft electric motor250 may operate any VFD voltage level that is adequate to continuouslydrive the single hydraulic pump 260 that will be apparent to thoseskilled in the relevant art(s) without departing from the spirit andscope of the disclosure.

For example, the power distribution trailer 120 may distribute theelectric power to the single VFD 240 at the power generation voltagelevel of 13.8 kV. The single VFD 240 may then convert the electric powerat the power generation voltage level of 13.8 kV to the VFD voltagelevel of 4160V to adequately drive the single shaft electric motor 250.The single shaft electric motor 250 may operate at an operatingfrequency of 60 Hz and when the VFD voltage level of 4160V to adequatelydrive the single shaft electric motor at the operating frequency of 60Hz, the single shaft electric motor 250 may then rotate at a RPM levelof at least 750 RPM. The single shaft electric motor 250 may rotate at aRPM level of at least 750 RPM based on the VFD voltage level of at least4160V as provided by the single VFD 240 and to drive the singlehydraulic pump 260 that is positioned on the single pump trailer 230with the single VFD 240 and the single shaft electric motor 250 with therotation at the RPM level of at least 750 RPM.

In an embodiment, the single shaft electric motor 250 may rotate at aRPM level of at least 750 RPM. In an embodiment, the single shaftelectric motor 250 may rotate at a RPM level of 750 RPM to 1400 RPM. Thesingle shaft electric motor 250 may operate at any RPM level tocontinuously drive the single hydraulic pump 260 that will be apparentto those skilled in the relevant art(s) without departing from thespirit and scope of the disclosure. The single shaft electric motor mayoperate at any operating frequency to continuously drive the singlehydraulic pump 260 that will be apparent to those skilled in therelevant art(s) without departing from the spirit and scope of thedisclosure.

The single shaft electric motor 250 may be an induction motor thatrotates at the RPM level needed to obtain required pump speed based onthe input gear box ratio of the single hydraulic pump 260. Based on theoperating frequency of the single shaft motor 250 and the VFD voltagelevel applied to the single shaft electric motor 250, the single shaftelectric motor 250 may then rotate at the required RPM level and producesufficient torque to cause the pump to produce the required flow rate offracking media at the required output pressure level. However, the VFDvoltage level applied to the single shaft electric motor 250 may bedetermined based on the input gear box ratio of the single hydraulicpump 260 as the single shaft electric motor 250 cannot be allowed torotate at the RPM level that exceeds the maximum speed rating of theinput gear box of the single hydraulic pump 260 or the maximum speed ofthe single hydraulic pump 260. The single shaft electric motor 250 maybe an induction motor, a traction motor, a permanent magnet motor and/orany other electric motor that continuously drives the single hydraulicpup 260 that will be apparent to those skilled in the relevant art(s)without departing from the spirit and scope of the disclosure.

As noted above, the single shaft electric motor 250 may be coupled to asingle hydraulic pump in the single hydraulic pump 260 and drive thesingle hydraulic pump 260 such that the single hydraulic pump 260continuously pumps the fracking media into the well to execute thefracking operation to prepare the well for the later extraction of thefluid from the existing well. The single hydraulic pump 260 may operateon a continuous duty cycle such that the single hydraulic pump 260continuously pumps the fracking media into the well. Rather thanoperating on an intermittent duty cycle that causes conventionalhydraulic pumps to temporarily stall in the pumping of the frackingmedia into the well, the single hydraulic pump 260 in operating on acontinuous duty cycle may continuously pump the fracking media into thewell without any intermittent stalling in the pumping. In doing so, theefficiency in the fracking operation to prepare the well for the laterextraction of the fluid from the well may significantly increase as anyintermittent stalling in pumping the fracking media into the well mayresult in setbacks in the fracking operation and may increase the riskof sand plugging the existing well. Thus, the single hydraulic pump 260in operating on the continuous duty cycle may prevent any setbacks inthe fracking operation due to the continuous pumping of the frackingmedia into the well.

The single hydraulic pump 260 may continuously pump the fracking mediainto the well at the HP level that the single hydraulic pump 260 israted. The increase in the HP level that the single hydraulic pump 260may continuously pump the fracking media into the well may result in theincrease in the efficiency in the fracking operation to prepare the wellfor later extraction of the fluid from the well. For example, the singlehydraulic pump 260 may continuously pump the fracking media into thewell at the HP level of at least 5000 HP as driven by the single shaftmotor 250 at the RPM level of at least 750 RPM. The single hydraulicpump 260 operates on a continuous duty cycle to continuously pump thefracking media at the HP level of at least 5000 HP. In an embodiment,the single hydraulic pump 260 may operate at continuous duty with a HPlevel of 5000 HP and may be a Weir QEM5000 Pump. However, the singlehydraulic pump 260 may any type of hydraulic pump that operates on acontinuous duty cycle and at any HP level that adequately continuouslypumps the pumping fracking media into the well to execute the frackingoperation to prepare the well for the later extraction of the fluid fromthe well that will be apparent to those skilled in the relevant art(s)without departing from the spirit and scope of the disclosure.

The single pump trailer 230 discussed in detail above may then beincorporated into the hydraulic fracking operation 100 depicted inFIG. 1. Each of the several pumps trailers 130(a-n), where n is aninteger equal to or greater than one, may be in incorporated into thehydraulic fracking operation 100 to increase the overall HP level thatis applied to the fracking equipment positioned on the fracking trailer170 by each of the single hydraulic pumps 160(a-n) positioned on each ofthe pump trailers 130(a-n). In doing so, the overall HP level that isapplied to the fracking equipment positioned on the fracking trailer 170to continuously pump the fracking media into the well may besignificantly increased as the HP level that is applied to the frackingequipment is scaled with each single hydraulic pump 160(a-n) that isadded to the hydraulic fracking operation 100.

The positioning of each single VFD 140(a-n), single shaft electric motor150(a-n), and each single hydraulic pump 160(a-n) positioned on eachcorresponding pump trailer 130(a-n) enables the power distributiontrailer 120 to distribute the electric power at the power generationvoltage level to each single VFD 140(a-n) from a single powerdistribution source rather than having a corresponding single powerdistribution source for each single VFD 140(a-n), single shaft electricmotor 150(a-n), and each single hydraulic pump 160(a-n). In doing so,the electric power at the power generation voltage level may bedistributed to each single VFD 140(a-n), where n is in an integer equalto or greater than one and corresponds to the number of pump trailers130(a-n), then each single VFD 140(a-n) may individually convert thepower generation voltage level to the appropriate VFD voltage for thesingle shaft electric motor 150(a-n) and the single hydraulic pump160(a-n) that is positioned on the corresponding pump trailer 130(a-n)with the single VFD 140(a-n). The single VFD 140(a-n) may then alsocontrol the corresponding single shaft electric motor 150(a-n) and thesingle hydraulic pump 160(a-n) that is positioned on the correspondingpump trailer 130(a-n) with the single VFD 140(a-n).

In isolating the single VFD 140(a-n) to convert the electric power atthe power generation voltage level to the appropriate VFD voltage levelfor the single shaft electric motor 150(a-n) and the single hydraulicpump 160(a-n) positioned on the corresponding single pump trailer130(a-n) as the single VFD 140(a-n), the capabilities of the single pumptrailer 130(a-n) may then be easily scaled by replicating the singlepump trailer 130(a-n) into several different pump trailers 130(a-n). Inscaling the single pump trailer 130(a-n) into several different pumptrailers 130(a-n), the parameters for the single VFD 140(a-n), thesingle shaft electric motor 150(a-n), and the single hydraulic pump160(a-n) may be replicated to generate the several different pumptrailers 130(a-n) and in doing so scaling the hydraulic frackingoperation 100.

In doing so, each single VFD 140(a-n) may convert the electric power atthe power generation voltage level as distributed by the powerdistribution trailer 120 to the VFD voltage level to drive each singleshaft electric motor 150(a-n), where n is an integer equal to or greaterthan one and corresponds to the quantity of single VFDs 140(a-n) andpump trailers 130(a-n), such that each single shaft electric motor150(a-n) rotates at the RPM level sufficient to continuously drive thesingle hydraulic pump 160(a-n) at the HP level of the single hydraulicpump 160(a-n). Rather than simply having a single hydraulic pump 260 asdepicted in FIG. 2 and discussed in detail above to continuously pump atthe HP level of the single hydraulic pump 260, several differenthydraulic pumps 160(a-n), where n is an integer equal to or greater thanone and corresponds to the to the quantity of single VFDs 140(a-n),single shaft electric motors 150(a-n) and pump trailers 130(a-n), aspositioned on different pump trailers 160 may be scaled together toscale the overall HP level that is provided to the fracking equipment aspositioned on the fracking trailer 170. In doing so, the overall HPlevel that is provided to the fracking equipment to continuously pumpthe fracking media into the well to execute the fracking operation toprepare the well for the later extraction of the fluid from the well maybe easily scaled by incorporating each of the individual pump trailers130(a-n) each with single hydraulic pumps 160(a-n) operating at the HPlevels to scale the HP levels of the single hydraulic pumps 160(a-n) togenerate the overall HP level for the hydraulic fracking operation 100.

For example, each of the single hydraulic pumps 160(a-n) positioned oneach corresponding pump trailer 130(a-n) may be operating on acontinuous duty cycle at a HP level of at least 5000 HP. A total ofeight pump trailers 130(a-n) each with a single hydraulic pump 160(a-n)positioned on the corresponding pump trailer 130(a-n) results in a totalof eight hydraulic pumps 160(a-n) operating on a continuous duty cycleat a HP level of at least 5000 HP. In doing so, each of the eighthydraulic pumps 160(a-n) continuously pump the fracking media into thewell at a HP level of at least 40,000 HP and do so continuously witheach of the eight hydraulic pumps 160(a-n) operating on a continuousduty cycle. Thus, the fracking media may be continuously pumped into thewell at a HP level of at least 40,000 HP to execute the frackingoperation to prepare the well for the later extraction of the fluid fromthe well. The hydraulic pumps 160(a-n) positioned on each correspondingpump trailer 130(a-n) may operate on a continuous duty at any HP leveland the and the quantity of pump trailers may be scaled to any quantityobtain an overall HP level for the hydraulic fracking operation 100 thatwill be apparent to those skilled in the relevant art(s) withoutdeparting from the spirit and scope of the disclosure.

Further, conventional hydraulic fracking operations that incorporatediesel engines require a diesel engine to drive each conventionalhydraulic pump rather than being able to consolidate the powergeneration to a power generation system 110 that consolidates thequantity and size of the gas turbine engines to generate the electricpower. Such an increase in diesel engines significantly increases thecost of the fracking operation in that significantly more trailersand/or significantly over size/weight trailers are required to transportthe diesel engines resulting in significantly more and/or specializedsemi-trucks and/or trailers required to transport the diesel engineswhich requires significantly more CDL drivers. As the overall assetcount increases at the fracking site, the overall cost increases due tothe increased amount of manpower required, the costs and delays relatedto permitted loads, as well as an increase in the amount of rigging thatis required to rig each of the diesel engines to the conventionalhydraulic pumps and so on. Rather, the electric driven hydraulicfracking operation 100 decreases the asset count by consolidating thepower generation to the gas turbine engines of decreased size andquantity that are consolidated into the power generation system 110. Thepower distribution trailer 120 then further decreases the cost byconsolidating the medium voltage cabling that is required to power eachof the assets thereby decreasing the amount of rigging required.

Further, conventional hydraulic fracking operations that incorporatediesel engines suffer significant parasitic losses throughout thedifferent components included in the fracking operation. Diesel enginesthat generate at a power level equal to the rated power level of theconventional fracking pumps may not result in delivering the full ratedpower to the pump due to parasitic losses throughout the conventionaldiesel fracking trailer configuraiton. For example, the diesel enginesmay suffer parasitic losses when driving the hydraulic coolers and thelube pumps that are associated with the conventional hydraulic pump inaddition to the parasitic losses suffered from driving the conventionalhydraulic pump itself. In such an example, the diesel engine may bedriving the conventional hydraulic pump that is rated at 2500 HP at theHP level of 2500 HP but due to parasitic losses, the diesel engine isactually only driving the conventional hydraulic pump at 85% of the HPlevel of 2500 HP due to the parasitic losses. However, the electricdriven hydraulic fracking operation 100 may have the single hydraulicpump 160(a-n) that is rated at the HP level of 5000 HP, however, theparasitic loads are controlled by equipment running in parallel with thesingle hydraulic pump 160(a-n), thus the single VFD 140(a-n) associatedwith each corresponding single hydraulic pump 160(a-n) provides all ofits output electric power to the single hydraulic pump 160(a-n), thesingle hydraulic pump 160(a-n) actually continuously pumps the frackingmedia into the well at 5000 HP. Thus, the asset count required for theelectric driven hydraulic fracking operation 100 is significantlyreduced as compared to the hydraulic fracking operations thatincorporate diesel engines due to the lack of parasitic losses for theelectric driven hydraulic fracking operation 100.

Further, the conventional hydraulic fracking operations that incorporatediesel engines generate significantly more noise than the electricdriven hydraulic fracking operation 100. The numerous diesel enginesrequired in the conventional hydraulic fracking operations generateincreased noise levels in that the diesel engines generate noise levelsat 110 Dba. However, the gas turbine engines incorporated into the powergeneration system 110 of the electric driven hydraulic frackingoperation 100 generate noise levels that are less than 85 Dba. Oftentimes, the fracking site has noise regulations associated with thefracking site in that the noise levels of the fracking operation cannotexceed 85 Dba. In such situations, an increased cost is associated withthe conventional hydraulic fracking operations that incorporate dieselengines in attempts to lower the noise levels generated by the dieselengines to below 85 Dba or having to build sound walls to redirect thenoise in order to achieve noise levels below 85 Dba. The electric drivenfracking operation 100 does not have the increased cost as the noiselevels of the oilfield gas turbine engines include silencers and stacks,thus they already fall below 85 Dba.

Further, the increase in the quantity of conventional hydraulic pumpsfurther increases the asset count which increases the cost as well asthe cost of operation of the increase in quantity of conventionalhydraulic pumps. Rather than having eight single hydraulic pumps160(a-n) rated at the HP level of 5000 HP to obtain a total HP level of40000 HP for the fracking site, the conventional hydraulic frackingsystems require sixteen conventional hydraulic pumps rated at the HPlevel of 2500 HP to obtain the total HP level of 40000 HP. In doing so,a significant cost is associated with the increased quantity ofconventional hydraulic pumps. Further, conventional hydraulic pumps thatfail to incorporate a single VFD 140(a-n), a single shaft electric motor150(a-n), and a single hydraulic pump 160(a-n) onto a single pumptrailer 130(a-n) further increase the cost by increasing additionaltrailers and rigging required to set up the numerous differentcomponents at the fracking site. Rather, the electric driven hydraulicfracking operation 100 incorporates the power distribution trailer 120to consolidate the power generated by the power generation system 110and then limit the distribution and the cabling required to distributethe electric power to each of the single pump trailers 130(a-n).

In addition to the fracking equipment positioned on the fracking trailer170 that is electrically driven by the electric power generated by thepower generation system 110 and each of the VFDs 140(a-n), single shaftelectric motors 150(a-n), and the single hydraulic pumps 160(a-n) thatare also electrically driven by the electric power generated by thepower generation system 110, a plurality of auxiliary systems 190 may bepositioned at the fracking site may also be electrically driven by theelectric power generated by power generation system 110. The auxiliarysystems 190 may assist each of the single hydraulic pumps 160(a-n) aswell as the fracking equipment positioned on the fracking trailer 170 aseach of the hydraulic pumps 160(a-n) operate to execute the frackingoperation to prepare the well for the later extraction of the fluid fromthe well. In doing so, the auxiliary systems 190 may be systems inaddition to the fracking equipment positioned on the fracking trailer170 and the single hydraulic pumps 160(a-n) that are required to preparethe well for the later execution of the fluid from the well.

For example, the auxiliary systems 190, such as a hydration system thatprovides adequate hydration to fracking media as the single hydraulicpumps 160(a-n) continuously pump the fracking media into the well. Thus,auxiliary systems 190 may include but are not limited to hydrationsystems, chemical additive systems, blending systems, sand storage andtransporting systems, mixing systems and/or any other type of systemthat is required at the fracking site that is addition to the frackingequipment positioned on the fracking trailer 170 and the singlehydraulic pumps 160(a-n) that may be electrically driven by the electricpower generated by the power generation system 110 that will be apparentto those skilled in the relevant art(s) without departing from thespirit and scope of the disclosure.

The electric power generated by the power generation system 110 may thusbe distributed by the power distribution trailer 120 such that theelectric power generated by the power generation system 110 may also beincorporated to power the auxiliary systems 190. In doing so, theelectric power generated by the power generation system 110 may beincorporated to not only drive the pump trailers 130(a-n) via the singleVFDs 140(a-n) positioned on each pump trailer 130(a-n) but to also powerthe auxiliary systems 190. Thus, the hydraulic fracking operation 100may be completely electric driven in that each of the required systemspositioned on the fracking site may be powered by the electric powergenerated by the electric power that is consolidated to the powergeneration system 110.

As noted above, each of the single VFDs 140(a-n) may include asophisticated control system that may control in real-time the operationof the single shaft electric motors 150(a-n) and the single hydraulicpumps 160(a-n) in order for the single shaft electric motors 150(a-n)and the single hydraulic pumps 160(a-n) to optimally operate tocontinuously pump the fracking media into the well to execute thefracking operation to prepare the well for the later extraction of thefluid from the well. However, the fracking control center 180 that maybe positioned at the fracking site and/or remote from the fracking sitemay also control the single VFDs 140(a-n) and in doing so control thereal-time operation of the single shaft electric motors 150(a-n) and thesingle hydraulic pumps 160(a-n) in order for the single shaft electricmotors 150(a-n) and the single hydraulic pumps 160(a-n) to optimallyoperate to continuously pump the fracking media into the well to executethe fracking operation to extract the fluid from the well. In doing so,the fracking control center 180 may intervene to control the single VFDs140(a-n) when necessary. The fracking control center 180 may alsocontrol the fracking equipment positioned on the fracking trailer 170 aswell as the auxiliary systems 190 in order to ensure that the frackingoperation is optimally executed to prepare the well for the laterextraction of the fluid from the well.

Communication between the fracking control center 180 and the singleVFDs 140(a-n), the fracking equipment positioned on the fracking trailer170, and/or the auxiliary systems 190 may occur via wireless and/orwired connection communication. Wireless communication may occur via oneor more networks 105 such as the internet or Wi-Fi wireless accesspoints (WAP. In some embodiments, the network 105 may include one ormore wide area networks (WAN) or local area networks (LAN). The networkmay utilize one or more network technologies such as Ethernet, FastEthernet, Gigabit Ethernet, virtual private network (VPN), remote VPNaccess, a variant of IEEE 802.11 standard such as Wi-Fi, and the like.Communication over the network 105 takes place using one or more networkcommunication protocols including reliable streaming protocols such astransmission control protocol (TCP), Ethernet, Modbus, CanBus, EtherCAT,ProfiNET, and/or any other type of network communication protocol thatwill be apparent from those skilled in the relevant art(s) withoutdeparting from the spirit and scope of the present disclosure. Wiredconnection communication may occur but is not limited to a fiber opticconnection, a coaxial cable connection, a copper cable connection,and/or any other type of direct wired connection that will be apparentfrom those skilled in the relevant art(s) without departing from thespirit and scope of the present disclosure. These examples areillustrative and not intended to limit the present disclosure.

Electric Power Distribution

FIG. 3 illustrates a block diagram of an electric driven hydraulicfracking system that provides an electric driven system to execute afracking operation in that the electric power is consolidated in a powergeneration system and then distributed such that each component in theelectric driven hydraulic fracking system is electrically powered. Anelectric driven hydraulic fracking system 300 includes a powergeneration system 310, a power distribution trailer 320, a plurality ofpump trailers 330(a-n), a plurality of single VFDs 340(a-n), aswitchgear configuration 305, a plurality of trailer auxiliary systems315(a-n), a plurality of switchgears 325(a-n), a switchgear transformerconfiguration 335, and fracking equipment 370. The electric power isconsolidated in the power generation system 310 and then distributed atthe appropriate voltage levels by the power distribution trailer 320 todecrease the medium voltage cabling required to distribute the electricpower. The single VFDs 340(a-n) and the trailer auxiliary systems315(a-n) positioned on the pump trailers 330(a-n) as well as thefracking control center 380 and auxiliary systems 390 are electricallypowered by the electric power that is consolidated and generated by thepower generation system 310. The electric driven hydraulic frackingsystem 300 shares many similar features with the hydraulic frackingoperation 100 and the single pump configuration 200; therefore, only thedifferences between the electric driven hydraulic fracking system 300and the hydraulic fracking operation 100 and single pump configuration200 are to be discussed in further detail.

As noted above, the power generation system 310 may consolidate theelectric power 350 that is generated for the electric driven hydraulicfracking system 300 such that the quantity and size of the power sourcesincluded in the power generation system 310 is decreased. As discussedabove, the power generation system 310 may include numerous powersources as well as different power sources and any combination thereof.For example, the power generation system 310 may include power sourcesthat include a quantity of gas turbine engines. In another example, thepower generation system 310 may include a power source that includes anelectric utility power plant that independently generates electric powerfor an electric utility grid. In another example, the power generationsystem 310 may include a combination of gas turbine engines and anelectric utility power plant. The power generation system 310 maygenerate the electric power 350 at a power level and a voltage level.

The power generation system 310 may generate electric power at a powergeneration voltage level in which the power generation voltage level isthe voltage level that the power generation system is capable ofgenerating the electric power 350. For example, the power generationsystem 310 when the power sources of the power generation system 310include a quantity of gas turbine engines may generate the electricpower 350 at the voltage level of 13.8 kV which is a typical voltagelevel for electric power 350 generated by gas turbine engines. Inanother example, the power generation system 310 when the power sourcesof the power generation system include an electric power plan maygenerate the electric power 350 at the voltage level of 12.47 kV whichis a typical voltage level for electric power 350 generated by anelectric utility power plant. The power generation system may generatethe electric power 350 at any voltage level that is provided by thepower sources included in the power generation system 310 that will beapparent to those skilled in the relevant art(s) without departing fromthe spirit and scope of the disclosure. The power generation system 310may then provide the electric power 350 at the power generation voltagelevel to the power distribution trailer 320 via a medium voltage cable.

In continuing for purposes of discussion, the power distribution trailer320 may then distribute the electric power 350 at the power generationvoltage level to a plurality of single VFDs 340(a-n), where n is aninteger equal to or greater than two, with each single VFD 340(a-n)positioned on a corresponding single trailer 330(a-n) from a pluralityof single trailers, where n is an integer equal to or greater than two.The power distribution trailer 320 may include a switchgearconfiguration 305 that includes a plurality of switchgears 325(a-n),where n is an integer equal to or greater than two, to distribute theelectric power 350 generated by the at least one power source includedin the power distribution trailer 310 at the power generation voltagelevel 360 to each corresponding single VFD 340(a-n) positioned on eachcorresponding trailer 330(a-n).

Since the electric power 350 is consolidated to the power generationsystem 310, the switch gear configuration 305 of the power distributiontrailer 320 may distribute the electric power 350 at the powergeneration voltage level as generated by the power generation system 310to each of the single VFDs 340(a-n) as electric power 360 at the powergeneration voltage level such that the each of the single VFDs 340(a-n)may then drive the single shaft electric motors and the single hydraulicpumps as discussed in detail below. For example, the switch gearconfiguration 305 of the power distribution trailer 320 may distributethe electric power 350 at the power generation voltage level of 13.8 kVto each of the single VFDs 340(a-n) as electric power 360 at the powergeneration voltage level of 13.8 kV when the power distribution system310 has power sources that include gas turbine engines. In anotherexample, the switch gear configuration 305 of the power distributiontrailer 320 may distribute the electric power 350 at the powergeneration level of 12.47 kV to each of the single VFDs 340(a-n) aselectric power 360 at the power generation level of 12.47 kV when thepower distribution 310 has power sources that include an electricutility power plant.

In order for the electric power to be consolidated to the powergeneration system 310 as well as to provide an electric driven system inwhich each of the components of the electric driven hydraulic frackingsystem 300 is driven by the electric power generated by the powergeneration system 310, the power distribution trailer 320 provides theflexibility to distribute the electric power 350 generated by the powergeneration system 310 at different voltage levels. In adjusting thevoltage levels that the electric power 350 generated by the powergeneration system 310 is distributed, the power distribution trailer 320may then distribute the appropriate voltage levels to several differentcomponents included in the electric driven hydraulic fracking system 300to accommodate the electric power requirements of the several differentcomponents included in the electric driven hydraulic fracking system300. For example, the power distribution trailer 320 may distribute theelectric power 360 generated by the power generation system 310 at thevoltage level of 13.8 kV as generated by the power generation system 310via the switch gears 325(a-n) to each of the single VFDs 340(a-n) forthe each of the single VFDs 340(a-n) to drive the single shaft electricmotors and the single hydraulic pumps. In another example, the powerdistribution trailer 320 may distribute the electric power 360 generatedby the power generation system 310 at the voltage level of 12.47 kV asgenerated by the power generation system 310 via the switch gears325(a-n) to each of the single VFDs 340(a-n) for each of the single VFDs340(a-n) to drive the single shaft electric motors and the singlehydraulic pumps.

However, the electric power distribution trailer 320 may also distributethe electric power 350 generated by the power generation system 310 at adecreased voltage level from the voltage level of the electric power 350originally generated by the power generation system 310. Severaldifferent components of the electric driven hydraulic fracking system300 may have power requirements that require electric power at asignificantly lower voltage level than the electric power 350 originallygenerated by the power generation system 310. In doing so, the powerdistribution trailer 320 may include a switchgear transformerconfiguration 335 that may step-down the voltage level of the electricpower 350 as originally generated by the power distribution trailer 310to a lower voltage level that satisfies the power requirements of thosecomponents that may not be able to handle the increased voltage level ofthe electric power 350 originally generated by the power distributiontrailer 310. In doing so, the electric power distribution trailer 320may provide the necessary flexibility to continue to consolidate theelectric power 350 to the power generation system 310 while stillenabling each of the several components to be powered by the electricpower generated by the power generation system 310.

For example, the switchgear transformer configuration 335 may convertthe electric power 350 generated by the at least one power source of thepower generation system 310 at the power generation voltage level to atan auxiliary voltage level that is less than the power generationvoltage level. The switchgear transformer configuration 335 may thendistribute the electric power 355 at the auxiliary voltage level to eachsingle VFD 340(a-n) on each corresponding single trailer 330(a-n) toenable each single VFD 340(a-n) from the plurality of single VFDs340(a-n) to communicate with the fracking control center 380. Theswitchgear transformer configuration 335 may also distribute theelectric power 355 at the auxiliary voltage level to a plurality ofauxiliary systems 390. The plurality of auxiliary systems 390 assistseach single hydraulic pump as each hydraulic pump from the plurality ofsingle hydraulic pumps operate to prepare the well for the laterextraction of the fluid from the well.

In such an example, the switchgear transformer configuration 335 mayconvert the electric power 350 generated by the power generation system310 with power sources include gas turbine engines at the powergeneration voltage level of 13.8 kV to an auxiliary voltage level of480V that is less than the power generation voltage level of 13.8 kV.The switchgear transformer configuration 335 may then distribute theelectric power 355 at the auxiliary voltage level of 480V to each singleVFD 340(a-n) on each corresponding single trailer 330(a-n) to enableeach single VFD 340(a-n) from the plurality of single VFDs 340(a-n) tocommunicate with the fracking control center 380. The switchgeartransformer configuration 335 may also distribute the electric power 355at the auxiliary voltage level of 480V to a plurality of auxiliarysystems 390. In another example, the switchgear transformerconfiguration 335 may convert the electric power 350 generated by thepower generation system 310 with power sources that include an electricutility power plant at the power generation voltage level of 12.47 kV toan auxiliary voltage level of 480V that is less than the powergeneration voltage level of 12.47 kV. In another example, the switchgeartransformer configuration 33 may convert the electric power 350 at thepower generation voltage level generated by the power generation system310 to the auxiliary voltage level of 480V, 120V, 24V and/or any otherauxiliary voltage level that is less than the power generation voltagelevel. The switchgear transformer configuration 335 may convert theelectric power 350 at the power generation voltage level generated bythe power generation system 310 to any auxiliary voltage level that isless than the power generation voltage level to assist each single VFD340(a-n) in executing operations that do not require the electric power360 at the power generation voltage level that will be apparent to thoseskilled in the relevant art(s) without departing from the spirit andscope of the disclosure.

Unlike each of the single VFDs 340(a-n) that may convert the electricpower 360 at the power generation voltage level to drive the singleshaft electric motors and the single hydraulic pumps, the frackingcontrol center 380, the auxiliary systems 390, the trailer auxiliarysystems 315(a-n) as well as the operation of features of the single VFDS340(a-n) that are unrelated to the driving of the single shaft electricmotors and the single hydraulic pumps require the electric power to bestepped down to the electric power 355 at the auxiliary voltage level.The switchgear transformer configuration 335 may provide the necessaryflexibility to step-down the electric power 360 at the power generationvoltage level to the generate the electric power 355 at the auxiliaryvoltage level such that the remaining components of the electric drivenhydraulic fracking system 300 may also be electrically driven by theelectric power consolidated to the power generation system 310.

In stepping down the electric power 350 generated by the powergeneration system 310 at the power generation voltage level, theswitchgear transformer configuration 335 may provide the electric power355 at the auxiliary voltage level to the auxiliary systems 390. Indoing so, the auxiliary systems 390 may be electrically driven by theelectric power 355 at the auxiliary voltage level such that the electricpower consolidated by the power generation system 310 may drive theauxiliary systems 390. The auxiliary systems 390 may include but are notlimited hydration systems, chemical additive systems, fracturingsystems, blending systems, mixing systems and so on such that each ofthe auxiliary systems 390 required to execute the fracking operation maybe electrically driven by the electric power consolidated by the powergeneration system 310. Further, the power distribution trailer 320 mayalso route a communication link 365 to each of the auxiliary systems 390such that the fracking control center 380 may intervene and control eachof the auxiliary systems 390 via the communication link 365 ifnecessary.

The switchgear transformer configuration 335 may also provide theelectric power 355 at the auxiliary voltage level to the frackingcontrol center 380. In providing the auxiliary voltage level to thefracking control center 380, the fracking control center 380 mayremotely control the auxiliary systems 390, the single VFDs 340(a-n), aswell as the trailer auxiliary systems 315(a-n) as requested by thefracking control center 380. The power distribution trailer 320 mayroute the communication link 365 to the auxiliary systems 390, thesingle VFDs 340(a-n), and the trailer auxiliary systems 315(a-n) suchthat the fracking control center 380 may communicate with each of theauxiliary systems 390, the single VFDs 340(a-n), and the trailerauxiliary systems 315(a-n) and thereby control via the communicationlink 365. As discussed above, the communication link 365 may be awireline and/or wireless communication link.

The switchgear transformer configuration 335 may also provide theelectric power 355 at the auxiliary voltage level to each of the singleVFDs 340(a-n). As discussed above and below, the single VFDs 340(a-n)convert the electric power 360 generated by the power generation system310 at the power generation voltage level to drive the single shaftelectric motors and the single hydraulic pumps. However, the single VFD340(a-n) may also operate with different functionality without having todrive the single shaft electric motors and the single hydraulic pumps.For example, the auxiliary systems 315(a-n) positioned on the pumptrailers 330(a-n) and/or included in the single VFDs 340(a-n) mayoperate as controlled by a corresponding VFD controller 345(a-n) that ispositioned on the corresponding single trailer 330(a-n) and associatedwith the corresponding single VFD 340(a-n).

In doing so, the single VFD controllers 345(a-n) may operate theauxiliary systems 315(a-n) when the single VFD 340(a-n) is simplyprovided the electric power 355 at the auxiliary voltage level ratherthan having to operate with the electric power 360 at the powergeneration voltage level. In doing so, the fracking control center 380may also communicate with the VFD controllers 345(a-n) and the singleVFDs 340(a-n) as well as the trailer auxiliary systems 315(a-n) via thecommunication link 365 when the stepped-down electric power 355 at theauxiliary voltage level is provided to each of the single VFDs 340(a-n).In addition to operating auxiliary systems 315(a-n) when thecorresponding single VFD 340(a-n) is provided the electric power 355 atthe auxiliary voltage level, the VFD controller 345(a-n) may alsooperate the trailer auxiliary systems 315(a-n) as well as control thecorresponding single shaft electric motor 150(a-n) that then drives eachof the corresponding hydraulic pumps 160(a-n) to continuously pump thefracking media into the well to execute the fracking operation toextract the fluid from the well when the electric power 360 at the powergeneration voltage level is provided to the single VFDs 340(a-n).

For example, the single VFDs 340(a-n) may operate at a reduced capacitywhen the switchgear transformer configuration 335 provides the electricpower 355 at the auxiliary voltage level. In doing so, the single VFDs340(a-n) may operate in a maintenance mode in which the electric power355 at the auxiliary voltage level is sufficient for the single VFDs340(a-n) to spin the single shaft electric motors but not sufficient todrive the single shaft electric motors at the RPM levels that the singleshaft electric motors are rated. In operating the single VFDs 340(a-n)in the maintenance mode with the electric power 355 at the auxiliaryvoltage level, the hydraulic pumps as well as the fracking equipment 370may be examined and maintenance may be performed on the hydraulic pumpsand the fracking equipment 370 to ensure the hydraulic pumps 160(a-n)and the fracking equipment 370 are operating adequately. The VFDcontrollers 345(a-n) of the single VFDs 340(a-n) may execute thefunctionality of the single VFDs 340(a-n) when operating in themaintenance mode. The fracking control center 380 may also remotelycontrol the single VFDs 340(a-n) via the communication link 365 toexecute the functionality of the single VFDs 340(a-n) when operating inthe maintenance mode.

In another example, the trailer auxiliary systems 315(a-n) may beoperated when the single VFDs 340(a-n) are operating at the reducedcapacity when the switchgear transformer configuration 335 provides theelectric power 355 at the auxiliary voltage level. The trailer auxiliarysystems 315(a-n) may be auxiliary systems positioned on the pumptrailers 330(a-n) and/or included in the single VFDs 340(a-n) such thatauxiliary operations may be performed on the single VFDs 340(a-n), thesingle shaft electric motors, and/or the single hydraulic pumps toassist in the maintenance and/or operation of the single VFDs 340(a-n)the single shaft electric motors and/or single hydraulic pumps when theelectric power 355 at the auxiliary voltage level is provided to thesingle VFDs 340(a-n). For example, the trailer auxiliary systems315(a-n) may include but are not limited to motor blower systems, thelube oil controls, oil heaters, VFD fans, and/or any other type ofauxiliary system that is positioned on the pump trailers 330(a-n) and/orincluded in the single VFDs 340(a-n) to assist in the maintenance and/oroperation of the single VFDs 340(a-n), single shaft electric motors,and/or single hydraulic pumps that will be apparent to those skilled inthe relevant art(s) without departing from the spirit and scope of thedisclosure.

VFD Configuration and Control

Returning to the electric power 350 that is generated by the powergeneration system 310 at the power generation voltage level and thendistributed by the power distribution trailer 320 as the electric power360 at the power generation voltage level to the single VFDs 340(a-n),the single VFDs 340(a-n) may convert electric power 360 at the powergeneration voltage level to a VFD voltage level that is adequate todrive the single shaft electric motors. As noted above for example, thesingle VFDs 340(a-n) may convert the electric power 360 at the powergeneration voltage level to a VFD voltage level at a range 0V to 6900Vto adequately drive the single shaft electric motors. In a specificembodiment the single VFDs 340(a-n) may convert the electric power atthe power generation voltage level to a VFD voltage level of 4160V toadequately drive the single shaft electric motors. In anotherembodiment, the single VFDs 340(a-n) may convert the electric power 360at the power generation voltage level to a VFD voltage level at a rangeof 4160V and greater.

In another embodiment, the single VFDs 340(a-n) may convert the electricpower 360 at the power generation voltage level to a VFD voltage levelat a range of at least 4160V to adequately drive the single shaftelectric motors. The single VFDs 340(a-n) may convert the electric power360 at the power generation voltage level to any VFD voltage level toadequately drive the single shaft electric motors that will be apparentto those skilled in the relevant art(s) without departing from thespirit and scope of the disclosure. Each single VFD 340(a-n) may includea phase shifting transformer that enables each single VFD 340(a-n) tooperate as a multi-cell VFD configuration. The multi-cell VFDconfiguration of each single VFD 340(a-n) may enable each single VFD340(a-n) to transition the AC voltage signal 360 that is associated withthe power generation voltage level as distributed by the powerdistribution trailer 320 to a VFD voltage signal that is associated withthe VFD voltage level.

Many conventional VFDs fail to adequately apply a sufficient amount ofphase changing sinusoidal signals to the conversion of the AC voltagesignal 360 at the power generation voltage level to the VFD voltagesignal at the VFD voltage level to achieve adequate levels of harmonicmitigation as the single VFDs 340(a-n) operate to drive thecorresponding single shaft electric motors and single shaft hydraulicpumps at the VFD voltage level when executing the fracking operation. Inan embodiment, the adequate elimination of harmonics from the operationof the VFD current waveform at the VFD voltage level is dictated byIEEE-519 that mandates the level of total harmonic distortion that isallowed in the VFD current waveform. Harmonics present in the VFDcurrent waveform that exceed the level of total harmonic distortionallowed by IEEE-519 is an excessive level of harmonics that areroutinely produced by the conventional VFDs. Harmonics present in theVFD current waveform that are below the level of total harmonicdistortion allowed by IEEE-519 results in having an adequate level ofharmonic mitigation. The level of harmonic mitigation such that thelevel of total harmonic distortion is at an adequate level may be anyadequate level that is acceptable to a power generation system 310 thatis providing power to the electric driven hydraulic fracking system 300that will be apparent to those skilled in the relevant art(s) withoutdeparting from the spirit and scope of the disclosure.

Thus, the conventional VFDs in often failing to adequately mitigate thelevel of harmonics when converting the AC voltage signal 360 at thepower generation voltage level to generate the VFD voltage signal at theVFD voltage level may result in the VFD current waveform failingIEEE-519. In doing so, the excess quantity of harmonics present in theconventional VFD current waveform propagate back through the AC voltagesignal 360 provided by the power distribution trailer 320 as well aspropagate back through the electric power 350 provided by the electricpower generation system 310. The propagation of the excess quantity ofharmonics back through to the electric power 350 provided by theelectric power generation system 310 may impose significant inefficiencyand may reduce the available level of the electric power 350 provided bythe electric power generation system 310 to the single hydraulic pumps260 and all other applications outside of the electric driven hydraulicfracking system 300 as well as cause thermal damage to the electricpower distribution architecture of the electric power generation system310 such as power lines, power cables and so on.

Rather than simply applying a limited amount of phase changing signalsto the AC voltage signal 360 at the power generation voltage level togenerate the VFD voltage signal at the VFD voltage level, the phaseshifting transformer included in the single VFDs 340(a-n) provides asignificant amount of phase shifted signals to the AC voltage signal 360to transition the AC voltage signal 360 to the VFD voltage signal. Theplurality of sinusoidal signals with each sinusoidal signal having aphase shift relative to each other may significantly decrease thequantity of harmonics caused in the VFD current waveform as the VFDs340(a-n) drive the corresponding single shaft electric motor and singlehydraulic pump at the VFD voltage level. In doing so, the quantity oftotal harmonic distortion allowed in the VFD current waveform byIEEE-519 may be satisfied due to the decreased quantity of harmonicscontent in the VFD current waveform.

In reducing the harmonics, the VFDs 340(a-n) assists to assure anacceptable decreased level of harmonic content at the point of commoncoupling such that the VFDs 340(a-n) may couple to an electric utilitypower plant such that the electric utility power plant may be the powergeneration system 310 and may provide the AC voltage signal 360 at thevoltage level of 12.47 kV to the VFDs 340(a-n). The electric utilitypower plant generates electric power for an electric utility grid. TheVFDs 340(a-n) in reducing the harmonics also assist to mitigate the riskthat the harmonic content may propagate onto the electric utility gridthereby satisfying the criteria necessary for the electric utility powerplant to act as the power generation system 310. Further, the reductionof the harmonics enables the VFDs 340(a-n) to operate at an improvedpower factor which throughout the complete load range thereby furtherreducing the cost for having the electric utility power plant to providepower to the VFDs 340(a-n) as the power generation system 310. Forexample, FIG. 4 illustrates a top-elevational view of a mobilesubstation for electric power provided by the electric utility powerplant as the power generation system 310. In doing so, an electricutility power plant configuration 400 may act as the power generationsystem 310 and/or in a combination with at least one gas turbine engineas the power generation system 310 due to the elimination of theharmonics and the operation at an improved power factor by the VFDs340(a-n).

More specifically, FIG. 5 illustrates a block diagram of an electricdriven hydraulic fracking system that provides an electric driven systemto execute a fracking operation in that a VFD configuration includes aplurality of VFD cells that are isolated in order to generate theelectric power at the VFD voltage level to drive the single shaft motor.An electric driven hydraulic fracking system 500 includes a VFDconfiguration 510 and a single shaft electric motor 530. The VFDconfiguration 510 includes a plurality of VFD cells 520(a-n), where n isan integer greater than one, a VFD transformer 540, a VFD relay 505, anda VFD controller 515. The VFD transformer 540 operates as a passivemeans for phase-shifting the three phase power source in that the VFDtransformer 540 provides the electric power 360 at the power generationvoltage level as 3-phase sinusoidal AC electric power with a first phase360 a, a second phase 360 b, and a third phase 360 c to each VFD cell520(a-n) and each VFD cell 520(a-n) then converts the 3-phase sinusoidalAC electric power 360(a-c) to AC electric power 550 at the VFD voltagelevel to drive the single shaft electric motor 530 based on the phaseshifting of the VFD transformer 540. The electric driven hydraulicfracking system 500 shares many similar features with the hydraulicfracking operation 100, the single pump configuration 200, and theelectric driven hydraulic fracking system 300; therefore, only thedifferences between the electric driven fracking system 500 and thehydraulic fracking operation 100, the single pump configuration 200, andthe electric driven hydraulic fracking system 300 are to be discussed infurther detail.

The VFD configuration 510 includes the VFD cells 520(a-n) in which eachof the VFD cells 520(a-n) are isolated from each other. The VFD cells520(a-n) are isolated from each other in that the VFD transformer 540may provide the electric power 360 at the power generation voltage levelto each VFD cell 520(a-n) as the 3-phase sinusoidal AC electric power360(a-c) individually as input power to each VFD cell 520(a-n). Forexample, the VFD transformer 540 may provide the first phase 360 a, thesecond phase 360 b, and the third phase 360 c of the 3-phase ACsinusoidal electric power 360(a-c) to the VFD cell 520 a as input power.The VFD transformer 540 may provide the first phase 360 a, the secondphase 360 b, and the third phase 360 c of the 3-phase AC sinusoidalelectric power 360(a-c) to the VFD cell 520 b as input power. The VFDtransformer 540 may provide the first phase 360 a, the second phase 360b, and the third phase 360 c of the 3-phase AC sinusoidal electric power360(a-c) to the VFD cell 520 n as input power and so on to each of theVFD cells 520(a-n) included in the VFD configuration 510.

Each of the VFD cells 520(a-n) are further isolated from each other inthat each of the VFD cells 520(a-n) include a plurality of windings.Each of the windings associated with each corresponding VFD cell520(a-n) enables each VFD cell 520(a-n) to receive the 3-phase ACsinusoidal electric power 360(a-c) as input power and then outputelectric power 560 at a VFD cell voltage level. In doing so, theelectric power 560 at the VFD cell voltage level that is generated as anoutput by each VFD cell 520(a-n) is isolated from each other output ofthe electric power 560 at the VFD cell voltage level of each other VFDcell 520(a-n). The isolation of the output of the electric power 560 atthe VFD cell voltage level of each VFD cell 520(a-n) may enable the3-phase AC sinusoidal electric power 360(a-c) to be segmented intonumerous different partitions based on the windings associated with eachVFD cell 520(a-n). As the windings associated with each VFD cell520(a-n) increase, the quantity of different partitions that each VFDcell 520(a-n) may segment the 3-phase AC sinusoidal electric power360(a-c) into also increases.

The segmenting of the 3-phase AC sinusoidal electric power 360(a-c) bythe windings associated with each of the VFD cells 520(a-n) may enableeach of the VFD cells 520(a-n) to generate partitions of the 3-phase ACsinusoidal electric power 360(a-c) in the electric power 560 at the VFDcell voltage level that may then be reconnected into a configuration togenerate the electric power 550 as a AC sinusoidal signal at the VFDvoltage level. For example, each of the VFD cells 520(a-n) may segmentthe 3-phase AC sinusoidal electric power 360(a-c) by windings associatedwith each of the VFD cells 520(a-n) to generate partitions of the3-phase AC sinusoidal electric power 360(a-c) as provided as theelectric power 560 at the VFD cell voltage level of 750V.

In such an example, each of the VFD cells 520(a-n) may include windingsthat may segment the 3-phase AC sinusoidal electric power 360(a-c) atthe power generation voltage level, of 13.8 kV for example, topartitions of electric power 560 at the VFD cell voltage level of 750V.The isolation of each of the VFD cells 520(a-n) may then enable thesingle VFD configuration 510 to then reconnect into a configuration ofeach of the partitions of electric power 560 at the VFD cell voltagelevel of 750V to generate the electric power 550 as a AC sinusoidalsignal at the VFD voltage level of 4160V which is necessary to drive thesingle shaft electric motor 530 in this example. The VFD cells 520(a-n)may segment the 3-phase AC sinusoidal electric power 360(a-c) at thepower generation voltage level into partitions of the electric power 560at the VFD cell voltage level at any VFD cell voltage level that may bereconnected into a configuration to generate the electric power 550 as aAC sinusoidal signal at the VFD voltage level required to adequatelydrive the single shaft electric motor 530 to execute the frackingoperation that will be apparent to those skilled in the relevant art(s)without departing from the spirit and scope of the disclosure.

The segmenting of the 3-phase AC sinusoidal electric power 360(a-c) bythe windings associated with each of the VFD cells 520(a-n) may alsoenable each of the VFD cells 520(a-n) to generate partitions of the3-phase AC sinusoidal electric power 360(a-c) in the electric power 560at the VFD cell voltage level that may then be reconnected into aconfiguration to generate the electric power 550 as a AC sinusoidalsignal at the VFD voltage level with increased smoothness. As notedabove, the increased quantity of windings associated with each of theVFD cells 520(a-n) may result in each of the VFD cells 520(a-n)generating an increase in partitions of the segmented 3-phase ACsinusoidal electric power 360(a-c) as provided in the electric power 560at the VFD cell voltage level. The subsequent reconnecting into aconfiguration of the partitions of the segmented 3-phase AC sinusoidalelectric power 360(a-c) as generated by the VFD cells 520(a-n) as theelectric power 560 at the VFD cell voltage level may then generate theelectric power 550 as a AC sinusoidal signal at the VFD voltage levelwith an increased smoothness.

As the partitions of the segmented 3-phase AC sinusoidal electric power360(a-c) as provided by the electric power 560 at the VFD cell voltagelevel are reconnected into a configuration to generate the electricpower 550 as a AC sinusoidal signal at the VFD voltage level, thesmoothness of the electric power 550 as the AC sinusoidal signal isimpacted based on the quantity of partitions generated by each of theVFD cells 520(a-n) of the segmented 3-phase AC sinusoidal electric power360(a-c). As the partitions generated by each of the VFD cells 520(a-n)of the segmented 3-phase AC sinusoidal electric power 360(a-c) due tothe isolation of the VFD cells 520(a-n) increases, the smoothness of theelectric power 550 as the AC sinusoidal signal also increases. As thepartitions generated by the each of the VFD cells 520(a-n) of thesegmented 3-phase AC sinusoidal electric power 360(a-c) decreases, thesmoothness of the electric power 550 as the AC sinusoidal signal alsodecreases. As mentioned above and will be discussed in detail below, theincrease in smoothness of the electric power 550 as the AC sinusoidalsignal decreases the quantity of harmonics present in the VFD currentwaveform of the electric power 550 at the VFD voltage level.

The VFD transformer 540 may provide a phase shift to each of thepartitions of the segmented 3-phase AC sinusoidal electric power360(a-c) as provided by the electric power 560 at the VFD cell voltagelevel as the partitions are reconnected into a configuration to generatethe electric power 560 as the AC sinusoidal signal at the VFD voltagelevel. The phase shifting of the each of the partitions of the segmented3-phase AC sinusoidal electric power 360(a-c) as generated by each ofthe VFD cells 520(a-n) by the VFD transformer 540 due to the isolationof each of the VFD cells 520(a-n) may further increase the smoothness ofthe electric power 550 as the AC sinusoidal signal. The VFD transformer540 may phase shift each of the partitions relative to each other suchthat the smoothness of the electric power 550 as the AC sinusoidalsignal is increased thereby decreasing the quantity of harmonics presentin the VFD current waveform of the electric power 550 at the VFD voltagelevel.

For example, the electric power 360 distributed by the powerdistribution trailer may be at a power generation voltage level of 12.47kV. The VFD transformer 540 may then provide the electric power 360 atthe power generation voltage level of 12.47 kV to each of the VFD cells520(a-n) as three-phase AC sinusoidal electric power 360(a-c). Each VFDcell 520(a-n) may include numerous windings. In such an example, thequantity of windings included in each VFD cell 520(a-n) may segment thethree-phase AC sinusoidal electric power 360(a-c) at the powergeneration voltage level of 12.47 kV into several different partitionssuch that each of the partitions are at a VFD cell voltage level of0.2*12.47 kV. In such an example, each of the partitions of thesegmented three-phase AC sinusoidal electric power 360(a-c) for eachcorresponding VFD cell when reconnected into a configuration may have aVFD cell voltage level of 750V for each VFD cell 520(a-n).

The single VFD configuration 510 may then reconnect into a configurationeach of the partitions that the windings included in each VFD cell520(a-n) of the segmented three-phase AC sinusoidal electric power360(a-c) at the VFD cell voltage level of 0.2*12.47 kV to generate theelectric power 550 at the VFD voltage level of 4160V in this examplethat is sufficient to drive the single shaft electric motor 530. Thesingle VFD configuration 510 may also reconnect into a configurationeach of the partitions that the windings included in each VFD cell520(a-n) provided at the VFD cell voltage level of 0.2*12.47 kV togenerate the AC sinusoidal electric power 550 at the VFD voltage levelsuch that the increased quantity of partitions increases the smoothnessof the AC sinusoidal electric power 550.

In doing so, the single VFD configuration 510 may reconnect theincreased quantity of partitions into a configuration that increases thesmoothness of the AC sinusoidal electric power to a threshold thatdecreases the quantity of total harmonics present in the VFD currentwaveform of the AC sinusoidal electric power 550. As a result, thequantity of total harmonic distortion allowed in the VFD currentwaveform of the AC sinusoidal electric power 550 by IEEE-519 may besatisfied due to the decreased quantity of harmonics in the VFD currentwaveform of the electric power 550. Further, the VFD transformer 540 mayphase shift the increased quantity of partitions of the segmentedthree-phase AC sinusoidal electric power 360(a-c) generated by each ofthe windings included in each of the VFD cells 520(a-n) at the VFD cellvoltage level of 0.2*12.47 kV such that the partitions are furtherreconnected into a configuration to also increase the smoothness of theAC sinusoidal electric power 550 to a threshold thereby decreasing thequantity of total harmonics present in the VFD current waveform of theAC sinusoidal electric power 550. As a result, the quantity of totalharmonic distortion allowed in the VFD current waveform of the ACsinusoidal electric power 550 by IEEE-519 may further be satisfied dueto the decreased quantity of harmonics in the current waveform of theelectric power 550.

However, the windings included in each of the VFD cells 520(a-n)provides flexibility as to the frequency and the VFD voltage level ofthe of the electric power 550. In doing so, the single VFD configuration510 is not limited in generating the electric power 550 at a single VFDvoltage level and frequency, such as 4160V at 60 Hz. Rather, thewindings included in each of the VFD cells 520(a-n) enable the singleVFD configuration 510 to reconnect into a configuration the partitionsof the segmented three-phase AC sinusoidal electric power 360(a-n) thatcustomizes the single VFD voltage level and frequency of the electricpower 550 to drive the single shaft electric motor 530. In doing so, thesingle VFD voltage level and frequency of the electric power 550 may bedecreased from the single VFD voltage level and frequency of 4160V at 60Hz as well as the single VFD voltage level and frequency of the electricpower 550 may be increased from the single VFD voltage level of 4160Vfrequency at 60 Hz.

The increased quantity of partitions generated by the windings of eachVFD cell 520(a-n) that segment the three-phase AC sinusoidal electricpower 360(a-n) into the electric power 560 at the VFD cell voltage levelfor each VFD cell 520(a-n) results in a sufficient amount of phasechanging sinusoidal signals represented in the partitions to convert thethree-phase sinusoidal AC signal 360(a-c) at the power generationvoltage level to the VFD voltage signal 550 at the VFD voltage level toachieve adequate levels of harmonic mitigation as the single VFDconfiguration 510 operates to drive the single shaft electric motor 530when executing the fracking operation. As noted above, the adequateelimination of harmonics from the operation of the VFD current waveformof the electric power 550 at the VFD voltage level is dictated byIEEE-519 that mandates the total harmonic distortion that is allowed inthe VFD current waveform of the electric power 550 at the VFD voltagelevel when driving the single shaft electric motor 530.

In decreasing the excess quantity of harmonics present on the VFDcurrent waveform of the electric power 550 at the VFD voltage level dueto the increased quantity of partitions of the segmented three-phase ACsinusoidal signal 360(a-c) as well as the phase shifting of suchpartitions, any excess quantity of harmonics present in the VFD currentwaveform of the electric power 550 that propagate back through the ACsinusoidal electric power 360 is sufficiently decreased to limitdisruption and minimize additional excess heat which is created byharmonics to the power generation system, such as the electric utilitypower grid. Further, decreasing the excess quantity of harmonics presenton the VFD current waveform of the electric power 550 at the VFD voltagelevel due to the increased quantity of partitions of the segmentedthree-phase sinusoidal signal 360(a-c) as well as the phase shifting ofsuch partitions may also sufficiently decrease the quantity of harmonicspresent in the VFD current waveform of the electric power to preventsignificant inefficiency and the reduction of the available level ofelectric power 350 provided by the power generation system 310 to thesingle shaft motor 530 and all other applications outside of theelectric drive hydraulic fracking system 300.

The quantity of VFD cells 520(a-n) may be any quantity of VFD cells520(a-n) such that the quantity of windings included in each of the VFDcells 520(a-n) enable the segmented three-phase sinusoidal signal360(a-c) to be segmented into a sufficient quantity of partitions suchthat the partitions may be reconnected into a configuration as well asphase-shifted to adequately decrease the quantity of harmonics presentin the VFD current waveform of the electric power 550 at the VFD voltagelevel to sufficiently satisfy IEEE-519 that will be apparent to thoseskilled in the relevant art(s) without departing from the spirit andscope of the disclosure.

FIG. 6 illustrates a block diagram of an electric driven hydraulicfracking system that provides an electric driven system to execute afracking operation in that a VFD configuration includes a plurality ofVFD cells that are electrically connected to a corresponding VFDcontactor from a plurality of VFD contactors in order to bypass a VFDcell that is no longer operating at its full capacity such that thefracking operation continues. An electric driven hydraulic frackingsystem 600 includes a VFD configuration 610, the power distributiontrailer 320, and the single shaft electric motor 530. The VFDconfiguration 610 includes the plurality of VFD cells 520(a-n), the VFDcontroller 515, and a plurality of VFD contactors 620(a-n), where n isan integer that is adequate to ensure that each VFD cell 520(a-n) may bebypassed if no longer operating at full capacity. The electric drivenhydraulic fracking system 600 shares many similar features with thehydraulic fracking operation 100, the single pump configuration 200, theelectric driven fracking system 300, and the electric driven frackingsystem 500; therefore, only the differences between the electric drivenfracking system 600 and the hydraulic fracking operation 100, the singlepump configuration 200, the electric driven hydraulic fracking system300, and the electric driven hydraulic fracking system 500 are to bediscussed in further detail.

As noted above, the power distribution trailer 320 may distributeelectric power 360 at the power generation voltage level to the VFDtransformer 540 and the VFD transformer 540 may then provide thethree-phase AC sinusoidal electric power 360(a-c) to each of the VFDcells 520(a-n). Each of the VFD cells 520(a-n) may then collectivelygenerate the electric power 550 at the VFD voltage level to drive thesingle shaft electric motor 530. The collective generation of theelectric power 550 at the VFD voltage level may be the electric power550 the VFD voltage level that is required to drive the single shaftelectric motor 530 at full capacity. In doing so, each of the VFD cells520(a-n) may be required to collectively generate the electric power 550at the VFD voltage level to drive the single shaft electric motor 530 atfull capacity. Any of the VFD cells 520(a-n) that may not be operatingat full capacity may result in the VFD cells 520(a-n) to collectivelyfail in generating the electric power 550 at the VFD voltage level todrive the single shaft electric motor 530 at full capacity.

For example, the electric power 550 at the VFD voltage level ascollectively generated by the VFD cells 520(a-n) may be 4160V in that4160V is required to drive the single shaft electric motor 530 at fullcapacity. In doing so, each of the VFD cells 520(a-n) may be required tocollectively generate the electric power 550 at the VFD voltage level of4160V. If the VFD cell 520 b fails to no longer operate at fullcapacity, the electric power 550 at the VFD voltage level may drop by1100V to 3060V. In doing so, the VFD cells 520(a-n) may no longer becollectively capable to generate the electric power at the VFD voltagelevel of 4160V to drive the single shaft electric motor 530 at fullcapacity.

Conventional electric driven fracking systems are not able to continueto execute the fracking operation when at least one of the conventionalVFD cells are no longer operating at full capacity. In such conventionalsystems, the conventional electric driven fracking systems shutdown whenat least one of the conventional VFD cells are no longer capable togenerate the electric power at the VFD voltage level necessary to drivethe single shaft electric motor at full capacity. In doing so,conventional electric driven fracking systems are required to remainshut down until the at least one conventional VFD cell is repairedand/or replaced thereby enabling the repaired and/or replacedconventional VFD cell to operate at full capacity such that the singleshaft electric motor may then be driven at full capacity collectively bythe conventional VFD cells. In doing so, the entire fracking operationalso shuts down and remains dormant until the at least one conventionalVFD cell is repaired in which such shut down periods may cost theoperating company millions of dollars in lost fracking time.

However, often times the conventional electric driven fracking systemmay still have the potential to continue the fracking operation at areduced capacity in that the single shaft electric motor 530 is drivenby electric power at a VFD voltage level that is reduced from the VFDvoltage level required to drive the single shaft electric motor 530 atfull capacity. However, the conventional electric driven frackingsystems are not capable of continuing to operate at a reduced capacityif at least one of the conventional VFD cells is no longer operating atfull capacity despite having the potential in the remaining conventionalVFD cells that are fully operational.

The conventional electric driven fracking systems are required to shutdown if at least one of the conventional VFD cells is no longeroperating at full capacity due to the conventional fracking systems nothaving an approach to bypass the at least conventional VFD cell that isno longer operating at full capacity thereby enabling the remainingconventional VFD cells to drive the single shaft electric motor at areduced capacity. Once the at least one conventional VFD cell fails tooperate at full capacity and is required to be deactivated, theconventional electric driven fracking system 600 cannot bypass thedeactivated conventional VFD such that the remaining conventional VFDsmay remain operational and drive the single shaft electric motor 530 ata reduced capacity to continue the fracking operation at a reducedcapacity. Thus, the conventional electric driving fracking systems liedormant without executing any type of fracking operation until the atleast one VFD cell is replaced and/or repaired and again costing theoperating company significant amounts for the time that the conventionalelectric driving fracking system lies dormant.

Rather than having to lie dormant whenever at least one of the VFD cells520(a-n) are not operating at full capacity until the at least one VFDcell 520(a-n) is repaired and/or replaced, the electrical drivenfracking system 600 may continue to operate at a reduced capacity suchthat the reduced capacity is still sufficient to generate the electricpower 550 at a reduced VFD voltage level that is sufficient to drive thesingle shaft electric motor 530 at the reduced capacity. In doing so,the electric driven fracking system 600 may continue the operation ofthe fracking operation despite having at least one VFD cell 520(a-n) notoperating at full capacity thereby enabling the operating company tocontinue to frack the fluid and not incur the financial loss ofremaining dormant until the at least one VFD cell 520(a-n) is repairedand/or replaced.

The single VFD 610 includes the plurality of VFD contactors 620(a-n).Each VFD contactor 620(a-n) may be positioned between a combination ofVFD cells 520(a-n) such that the corresponding VFD contactor 620(a-n)operates as a bypass for the electric power 550 at the reduced VFDvoltage level when a corresponding VFD cell 520(a-n) is no longeroperating at full capacity. The VFD controller 515 may continuouslymonitor parameters associated with each of the VFD cells 520(a-n) viathe communication link 365 as the VFD cells 520(a-n) operate to generatethe electric power 550 at the VFD voltage level to drive the singleshaft electric motor 530 at full capacity. The generation of theelectric power 550 at the VFD voltage level to drive the single shaftelectric motor 530 at full capacity by the VFD cells 520(a-n) is greaterthan the electric power 550 at the reduced voltage level generated bythe VFD cells 520(a-n) when not driving the single shaft electric motor530 at full capacity. For example, the VFD cells 520(a-n) may generatethe electric power 550 at the VFD voltage level of 4160V when drivingthe single shaft electric motor 530 at full capacity such that the VFDvoltage level of 4160V is greater than the electric power 550 at thereduced VFD voltage level generated by the VFD cells 520(a-n) when notdriving the single shaft electric motor 530 at full capacity. In such anexample, the VFD cells 520(a-n) may not drive the single shaft electricmotor 530 at full capacity when generating the electric power 550 at thereduced voltage level of 3060V.

The VFD controller 515 may continuously monitor parameters associatedwith each of the VFD cells 520(a-n) via the communication link 365 asthe VFD cells 520(a-n) operate to generate the electric power 550 at theVFD voltage level to drive the single shaft electric motor 530 at fullcapacity. The VFD controller 515 may then determine if any of theparameters associated with each of the VFD cells 520(a-n) deviate toindicate that at least one of the VFD cells 520(a-n) is no longeroperating at full capacity and may be a risk to the execution of thefracking operation if the at least one VFD cell 520(a-n) continues toremain operational during the fracking operation. Rather than have todeactivate the electric driven fracking system 600 thereby shutting downthe fracking operation until the at least one VFD cell 520(a-n) isrepaired and/or replaced, the VFD controller 515 may instruct via thecommunication link 365 the VFD contactor 620(a-n) associated with the atleast one VFD cell 520(a-n) that is no longer operating at full capacityto transition from an open state to a closed state.

In transitioning from the open state to the closed state, the VFDcontactor 620(a-n) that is associated with the VFD cell 520(a-n) that isno longer operating at full capacity may operate as a short circuit anddivert the electric power 550 at the reduced VFD voltage level frompropagating through the VFD cell 520(a-n) that is no longer operating atfull capacity. In doing so, the VFD contactor 620(a-n) that is in theclosed position and operating as the short circuit may then act as abypass for the electric power 550 at the reduced VFD voltage level tobypass the VFD cell 520(a-n) that is no longer operating at fullcapacity and continue to propagate to the remaining VFD cells 520(a-n).In doing so, the remaining VFD cells 520(a-n) that are operating at afull capacity may continue to generate the electric power 550 at thereduced VFD voltage level and continue to drive the single shaftelectric motor 530 at a reduced capacity that is sufficient to continueto adequately continue the fracking operation thereby preventing theoperating company from having to incur the financial loss of thefracking operation lying dormant.

The VFD controller 515 may continue to maintain the remaining VFDcontactors 620(a-n) that are associated with the remaining VFD cells520(a-n) that are operating at full capacity in the open state. In doingso, the electric power 550 at the reduced VFD voltage level that isgenerated by the remaining VFD cells 520(a-n) may continue to have suchelectric power 550 propagate through. In doing so, the remaining VFDcells 520(a-n) may continue to contribute to the generation of theelectric power 550 at the reduced VFD voltage level. The reduced VFDvoltage level is the electric power 550 with a reduced VFD voltage levelthat is less than the electric power 550 with the VFD voltage level thatis generated when each of the VFD cells 520(a-n) are operating at fullcapacity.

As each VFD cell 520(a-n) is bypassed, the electric power 550 is reducedto a reduced VFD voltage level that is equivalent to the bypassed VFDcell 520(a-n) no longer contributing to the generation of the electricpower 550 at the VFD voltage level when each of the VFD cells 520(a-n)are operating at full capacity. For example, a total of VFD cells520(a-n) included in the single VFD 610 is three. The electric power 550at the VFD voltage level generated when each of the three VFD cells520(a-n) operate at full capacity is 4160V. The electric power 550 atthe reduced VFD voltage level generated when one of the three VFD cells520(a-n) is bypassed by the corresponding VFD contactor 620(a-n) isreduced by 33% of the electric power 550 at the VFD voltage level whenall three VFD cells 520(a-n) are operating at full capacity. Thus, theelectric power 550 at the reduced VFD voltage level is 33% of 4160V or3060V in such an example.

The single shaft electric motor 530 may continue to operate at asufficient level to execute the fracking operation when at least one ofthe VFD cells 520(a-n) is bypassed by the corresponding VFD contactor620(a-n). Although the remaining VFDC cells 520(a-n) may provide theelectric power 550 at the reduced VFD voltage level, such a reduced VFDvoltage level may enable the single shaft electric motor 530 to operateat full torque but with a reduced speed and power level of the electricpower 550 at the reduced VFD voltage level. In doing so, the singleshaft electric motor 530 may continue to operate at full torque due thecurrent capability of the VFD cells 520(a-n) and thereby maintain thefracking operation while operating at a reduced speed and reduced power.Thus, the fracking operation may continue without interruption as thebypassed VFD cell 520(a-n) is repaired and/or replaced due to thecorresponding VFD contactor 620(a-n) bypassing the VFD cell 520(a-n)that is not operating at full capacity.

The VFD controller 515 may then continue to monitor the bypassed VFDcell 520(a-n) via the communication link 365. Once the operationcontroller 515 determines that the bypassed VFD cell 520(a-n) currentlysatisfies the appropriate parameters, the VFD controller 515 mayinstruct the corresponding VFD contactor 620(a-n) to transition from theclosed state to the open state via the communication link 365. After thecorresponding VFD contactor 620(a-n) transitions from the closed stateto the open state, then the electric power 550 at the VFD voltage levelmay propagate through the replaced and/or repaired VFD cell 520(a-n) dueto the corresponding 620(a-n) transitioning from the closed state to theopen state thereby eliminating the short circuit. Each of the VFD cells520(a-n) may the automatically generate the electric power 550 at theVFD voltage level rather than the reduced VFD voltage level and thesingle shaft electric motor 530 may automatically transition tooperating at full capacity with the electric power 550 at the VFDvoltage level. In doing so, the VFD cell 520(a-n) that was previouslynot operating at full capacity may be repaired and/or replaced withoutdisrupting the fracking operation and then transitioned back intooperating at full capacity triggering the electric power 550 toautomatically increase back up to the VFD voltage level from the reducedVFD voltage level.

As noted above, each of the VFD cells 520(a-n) may be isolated from eachother. The isolation of each of the VFD cells 520(a-n) enables theneutral point of all of the VFD cells 520(a-n) when generating theelectric power 550 at the VFD voltage level relative to the single shaftelectric motor 530 to not be tied to ground of the single VFD 610. Theisolation of each of the VFD cells 520(a-n) may enable the neutral pointof all of the VFD cells 520(a-n) to float rather than be tied to groundof the single VFD 610. In doing so, any VFD cell 520(a-n) that is thensubsequently bypassed by the corresponding VFD contactor 620(a-n) maythen move the neutral point of the electric power 550 at the reduced VFDvoltage level generated by the remaining VFD cells 520(a-n) that areoperating at full capacity. However the moving of the neutral point isirrelevant to the operation of the single shaft electric motor 530 dueto the neutral point not being tied to ground of the single VFD 610.Thus, any of the VFD cells 520(a-n) may easily be bypassed and theelectric power 550 at the reduced voltage level may automatically begenerated by the remaining VFD cells 520(a-n) without impacting theoperation of the single shaft electric motor 530.

Returning to FIG. 5, the VFD transformer 540 may receive the electricpower 355 at the auxiliary voltage level and may pre-charge thecapacitors associated with each of the VFD cells 520(a-n) before the VFDcontroller 515 transitions the VFD relay 505 from the open state to theclosed state. The VFD cells 520(a-n) when collectively activated by thethree-phase AC sinusoidal electric power 360(a-c) at the powergeneration voltage level may generate a significant in-rush of currentdue to the significant amount of current that each of the VFD cells520(a-n) may collectively generate once activated by the three-phase ACsinusoidal electric power 360(a-c) at the power generation voltagelevel. The significant in-rush of current collectively generated by eachof the VFD cells 520(a-n) once activated by the three-phase ACsinusoidal electric power 360(a-c) at the power generation voltage levelmay then propagate back to the power generation system 310 and have anegative impact on the power generation system 310. The VFD relay 505may remain in the open state to prevent each of the VFD cells 520(a-n)from being exposed to the three-phase AC sinusoidal electric power360(a-c) and in doing so prevent the significant in-rush of current fromoccurring.

For example, the power generation system 310 is an electric utilitypower plant that generates the electric power 360 at the powergeneration voltage level of 12.47 kV and provides such electric power350 to the power distribution trailer 320 to be distributed to thesingle VFD 340(a-n). The electric utility power plant 310 often timesindependently generates electric power for an electric utility grid. Asignificant in-rush of current generated from each single VFD 340(a-n)after each single VFD 340(a-n) is activated by the electric power 360 atthe power generation voltage level of 12.47 kV that is then propagatedback to the electric utility power plant 310 may negatively impact theelectric utility grid that the electric utility power plant 310independently generates electric power for. Thus, the operators of theelectric utility power plant 310 require that the in-rush of currentthat is propagated back to the electric utility power plant 310generated by each single VFD 340(a-n) be significantly mitigated. As aresult, the VFD relay 505 may remain in the open state to prevent thethree-phase AC sinusoidal electric power 360 at the power generationlevel of 12.47 kV from propagating to the VFD cells 520(a-n) therebypreventing the significant in-rush of current from propagating back tothe electric utility power plant 310.

In order to significantly mitigate the in-rush of current that ispropagated back to the power generation system 310 after the single VFDconfiguration 510 is activated by the electric power 360 at the powergeneration voltage level, the VFD transformer 540 may operate topre-charge the capacitors associated with each of the VFD cells 520(a-n)before exposing each of the VFD cells 520(a-n) to the three-phase ACsinusoidal electric power 360(a-c) at the power generation voltagelevel. The switchgear transformer 335 may provide the electric power 355at the auxiliary voltage level to the VFD transformer 540. The VFDtransformer 540 may isolate each of the VFD cells 520(a-n) from thethree-phase AC sinusoidal electric power 360(a-c) at the powergeneration voltage level while the VFD transformer 540 pre-charges thecapacitors associated with each of the VFD cells 520(a-n) with theelectric power 355 at the auxiliary voltage level as provided by theswitchgear transformer 335. The VFD transformer 540 may then activateeach corresponding VFD cell 520(a-n) with the electric power 355 at theauxiliary voltage level by pre-charging the capacitors associated witheach VFD cell 520(a-n) with the electric power 355 at the auxiliaryvoltage level. The VFD controller 515 may maintain the VFD relay 505 inthe open state to prevent the three-phase AC sinusoidal electric power360 at the power generation voltage level from propagating to the VFDcells 520(a-n) as the capacitors associated with each of the VFD cells520(a-n) pre-charge.

In doing so, each VFD cell 520(a-n) may essentially be exposed to theelectric power 355 at the auxiliary voltage level and pre-charge to avoltage threshold of the electric power 360 at the power generationvoltage level. For example, the each VFD cell 520(a-n) may pre-chargewith the electric power 355 at the auxiliary voltage level to thevoltage threshold of 20% to 25% of the electric power 360 at the powergeneration voltage level. The voltage threshold may be any percentage ofthe electric power 360 at the power generation voltage level that eachVFD cell 520(a-n) is to pre-charge to prevent an in-rush of current thatmay negatively impact the power generation system 310 that will beapparent to those skilled in the relevant art(s) without departing fromthe spirit and scope of the disclosure. As each VFD cell 520(a-n)pre-charges with the auxiliary voltage level, the VFD controller 515 maymonitor the pre-charge of the capacitors associated with each of the VFDcells 520(a-n) via the communication link 365. The VFD controller 515monitor the pre-charge of the capacitors associated with each VFD cell520(a-n) to determine whether the pre-charge has reached the voltagethreshold of the electric power 360 at the power generation voltagelevel. The VFD controller 515 may continue to maintain the VFD relay inthe open position preventing the electric power 360 at the powergeneration voltage level from propagating to the VFD cells 520(a-n) whenthe voltage threshold has not been reached.

After the VFD controller 515 has determined that the capacitorsassociated with each of the VFD cells 520(a-n) have pre-charged to thevoltage threshold via the communication link 365 from the electric power355 at the auxiliary voltage level as provided by the switchgeartransformer 335, the VFD controller 515 may then transition the VFDrelay 505 from the open position to the closed position via thecommunication link 365. The transition of the VFD relay 505 from theopen position to the closed position may enable the VFD transformer toprovide the three-phase AC sinusoidal electric power 360(a-c) to each ofthe VFD cells 520(a-n). In doing so, each VFD cell 520(a-n) may then bepowered by the three-phase AC sinusoidal electric power 360(a-c) at thepower generation voltage level and thereby generate the electric power550 at the VFD voltage level to drive the single shaft electric motor530.

However, the in-rush of current that may propagate back to the powergeneration system 310 may be significantly reduced due to the pre-chargeof the capacitors of each of the VFD cells 520(a-n) due to the VFDcontroller 515 maintaining the VFD relay 505 in the open state. In doingso, the VFD controller 515 limits the VFD cells 520(a-n) to beingexposed to the electric power 355 at the auxiliary voltage level andprevents the VFD cells 520(a-n) from being exposed to the electric power360 at the power generation voltage level 360 until each of thecapacitors associated with the VFD cells 520(a-n) has pre-charged to thevoltage threshold of the electric power 360 at the power generationvoltage level. Thus, any negative impact to the power generation system310 after each single VFD 340(a-n) is exposed to the electric power 360at the power generation voltage level is significantly decreased.

For example, the power generation system 310 is an electric utilitypower plant that generates the electric power 360 at the powergeneration voltage level of 12.47 kV. The VFD controller 515 maymaintain the VFD relay 505 in the open state via the communication link365 as the VFD transformer 540 provides the electric power 355 at theauxiliary voltage level of 480V to the VFD cells 520(a-n) as provided bythe switchgear transformer 335. The VFD controller 515 may maintain theVFD relay 505 in the open state to prevent the VFD cells 520(a-n) frombeing exposed to the three-phase AC sinusoidal electric power 360 at thepower generation level of 12.47 kV to protect the electric utility powerplant 310 from experiencing any in-rush current from the VFD cells520(a-n) before the capacitors of the VFD cells 520(a-n) have beenpre-charged to a voltage threshold of 20% of the electric power 360 atthe power generation voltage level of 12.47 kV.

The VFD controller 515 may continue to monitor the VFD cells 520(a-n)via the communication link 365 to determine whether the capacitorsassociated with the VFD cells 520(a-n) has reached the voltage thresholdof 20% of the electric power 360 at the power generation voltage levelof 12.47 kV. The VFD controller 515 may then transition the VFD relay505 from the open state to the closed state via the communication link365 when the VFD controller 365 determines that each of the capacitorsassociated with the VFD cells 520(a-n) has pre-charged to the voltagethreshold of 20% of the electric power at the power generation voltagelevel of 12.47 kV. In doing so, the VFD controller 515 may enable theVFD cells 520(a-n) to be exposed to the three-phase AC sinusoidalelectric power 360(a-c) at the power generation voltage level of 12.47kV. However, any in-rush current that the electric utility power plantmay be exposed to may be prevented due to the pre-charge of thecapacitors to the voltage threshold of 20% of the electric power 360 atthe power generation voltage level of 12.47 kV before being exposed tothe electric power 360 at the power generation voltage level of 12.47kV.

In an embodiment, the VFD transformer 540 may pre-magnetize via theelectric power 355 at the auxiliary voltage level as provided by theswitchgear transformer 335. In doing so, the VFD controller 515 maymonitor the pre-magnetization of the VFD transformer 540 via thecommunication link 365 to determine whether the pre-magnetization of theVFD transformer has reached a pre-magnetization threshold. Thepre-magnetization threshold is the threshold of pre-magnetization of theVFD transformer 540 that when reached and/or exceeded may prevent theVFD cells 520(a-n) from generating an in-rush current that may propagateback to the power generation system 310 and cause disruption to thepower generation system 310. The VFD controller 515 may continue tomaintain the VFD relay 505 in the open state to prevent the electricpower 360 at the power generation voltage level from propagating to theVFD cells 520(a-n) when the pre-magnetization of the VFD transformer 540is yet reach the pre-magnetization threshold. The VFD relay 505 may thentransition the VFD relay 505 from the open state to the closed statewhen the VFD controller 515 determines that the pre-magnetization of theVFD transformer 540 has reached the pre-magnetization threshold therebyenabling the three-phase AC sinusoidal electric power 360 at the powergeneration voltage level to propagate to the VFD cells 520(a-n).

The VFD transformer 540 may include a sure power connection in that theVFD transformer 540 may be plugged into a building power connection thatprovides electric power at a building power voltage that is typical forbuildings. The electric power at the building power voltage issignificantly lower than the electric power 360 at the power generationvoltage level as well as the electric power 355 at the auxiliary voltagelevel. However, often times, the VFD configuration 510 may lie dormantwhen not engaged in a fracking operation. When not engaged with afracking operation, there is no reason to waste electric power byproviding the VFD configuration 510 with electric power 360 at the powergeneration voltage level and/or the electric power 355 at the auxiliaryvoltage level. Further, the VFD configuration 510 may not be positionedat the fracking site as is the power distribution trailer 320 to evenhave the opportunity to be powered by the electric power 360 at thepower generation level and/or the electric power 355 at the auxiliaryvoltage level.

However, during the time period 510 that the VFD configuration 510 liesdormant and is not engaged in a fracking operation, maintenance may beperformed on the VFD configuration 510. The VFD transformer 540 with thesure power connection enables the VFD configuration 510 to be powered bythe electric power at the building power voltage such that themaintenance may be easily performed without wasting any unnecessaryelectric power provided by the electric power 360 at the powergeneration voltage level and/or the electric power 355 provided by theauxiliary voltage level. Further, the VFD configuration 510 may beparked outside and exposed to the environmental elements during the timeperiod that the VFD configuration 510 lies dormant. The VFD transformer540 with the sure power connection enables the VFD configuration 510 tobe easily powered by the electric power at the building power voltagesuch that the heaters, the fans, and all other environmental featuresincluded in the VFD configuration 510 may be activated to preventmoisture from accumulating inside the VFD configuration 510 to maintaina quality environment for the VFD configuration 510 as the VFDconfiguration 510 lies dormant.

CONCLUSION

It is to be appreciated that the Detailed Description section, and notthe Abstract section, is intended to be used to interpret the claims.The Abstract section may set forth one or more, but not all exemplaryembodiments, of the present disclosure, and thus, is not intended tolimit the present disclosure and the appended claims in any way.

The present disclosure has been described above with the aid offunctional building blocks illustrating the implementation of specifiedfunctions and relationships thereof. The boundaries of these functionalbuilding blocks have been arbitrarily defined herein for the convenienceof the description. Alternate boundaries may be defined so long as thespecified functions and relationships thereof are appropriatelyperformed.

It will be apparent to those skilled in the relevant art(s) the variouschanges in form and detail can be made without departing from the spirtand scope of the present disclosure. Thus the present disclosure shouldnot be limited by any of the above-described exemplary embodiments, butshould be defined only in accordance with the following claims and theirequivalents.

What is claimed is:
 1. An electric driven hydraulic fracking system thatpositions a single variable frequency drive (VFD), a single shaftelectric motor, and a single hydraulic pump mounted on a single pumptrailer to pump a fracking media into a well to execute a frackingoperation to extract a fluid from the well, comprising: a powergeneration system that is configured to generate electric power at apower generation voltage level; a power distribution trailer that isconfigured to distribute the electric power generated by powergeneration system at the power generation voltage level and electricpower at an auxiliary voltage level to a single VFD configuration on thesingle pump trailer, wherein the electric power at the auxiliary voltagelevel controls an operation of a plurality of auxiliary systemsassociated with the single pump trailer; and a pump configuration thatincludes the single VFD configuration, the single shaft electric motor,and the single hydraulic pump mounted on the single pump trailer,wherein: the single VFD configuration is configured to: convert theelectric power at the power generation voltage level distributed fromthe power distribution trailer to a VFD voltage level and drive thesingle shaft electric motor to control the operation of the single shaftelectric motor and the single hydraulic pump, wherein the VFD voltagelevel is a voltage level that is required to drive the single shaftelectric motor, and control operation of the plurality of auxiliarysystems based on the electric power at the auxiliary voltage level,wherein: the single VFD configuration includes a plurality of VFD cellswith each VFD cell isolated from each other VFD cell and configured tosegment the electric power at the power generation voltage level into aplurality of partitions, wherein each partition when reconnected into aconfiguration generates electric power at the VFD voltage level to drivethe single shaft electric motor with a decrease in harmonics included ina VFD current waveform of the electric power at the VFD voltage level.2. The electric driven hydraulic fracking system of claim 1, wherein theVFD configuration further comprises: a VFD transformer that isconfigured to apply a phase shift to each of the partitions generatedfrom the segmentation of the electric power at the power generationvoltage level by each of the VFD cells isolated from each other VFDcell, wherein the phase shift applied to each partition when reconnectedinto the configuration generates electric power at the VFD voltage levelto drive the single shaft electric motor with a decrease in harmonicsincluded in a VFD current waveform of the electric power at the VFDvoltage level.
 3. The electric driven hydraulic fracking system of claim2, wherein the VFD transformer is further configured to: receive theelectric power at the power generation voltage level and the electricpower at the auxiliary voltage level as distributed by the powergeneration trailer; and pre-charge a plurality of capacitors associatedwith each of the VFD cells to a voltage threshold with the electricpower at the auxiliary voltage level to prevent an in-rush current thatpropagates to the power generation system after the VFD transformerprovides the electric power at the power generation voltage level toeach of the VFD cells before the capacitors are pre-charged to thevoltage threshold, wherein the voltage threshold is a percentage of thepower generation voltage level that the capacitors are to be pre-chargedto prevent the in-rush current after the VFD transformer provides theelectric power at the power generation voltage level.
 4. The electricdriven hydraulic fracking system of claim 3, wherein the VFDconfiguration further comprises: a VFD relay that is configured to:prevent the electric power at the power generation voltage level frompropagating to each of the VFD cells when the VFD relay is in an openstate; and allow the electric power at the power generation voltagelevel to propagate to each of the VFD cells when the VFD relay is in aclosed state.
 5. The electric driven hydraulic fracking system of claim3, wherein the VFD configuration further comprises: a VFD controllerthat is configured to: monitor the capacitors associated with each ofthe VFD cells to determine whether the pre-charge of each of thecapacitors satisfies the voltage threshold, maintain the VFD relay inthe open state when the pre-charge of each of the capacitors associatedwith each of the VFD cells is below the voltage threshold to prevent theelectric power at the power generation voltage level from propagating toeach of the VFD cells, and transition the VFD relay from the open stateto the closed state when the pre-charge of each of the capacitorsassociated with each of the VFD cells satisfies the voltage threshold toenable the electric power at the power generation voltage level topropagate to each of the VFD cells.
 6. The electric driven hydraulicfracking system of claim 5, wherein the VFD configuration furthercomprises: at least one VFD contactor with each VFD contactorelectrically connected to two different VFD cells and is configured to:enable the two different VFD cells that the at least one VFD contactoris electrically connected to continue to operate in generating theelectric power at the VFD voltage level to drive the single shaftelectric pump at a full capacity, wherein the single shaft electric pumpis driven at a full capacity when each of the VFD cells included in theVFD configuration operate in generating the electric power at the VFDvoltage level to drive the single shaft electric pump at the fullcapacity, bypass at least one of the two different VFD cells the atleast one VFD contactor is electrically connected to prevent the atleast one of the two different VFD cells from generating the electricpower at the VFD voltage level to drive the single shaft electric pumpat the full capacity, wherein each VFD cell included in the VFDconfiguration that is not bypassed by the at least one VFD contactorcontinue to operate in generating the electric power at a reduced VFDvoltage level that is less than the electric power at the VFD voltagelevel to drive the single shaft electric pump at a reduced capacity thatis less than the full capacity.
 7. A method for an electric drivenhydraulic fracking system that positions a single variable frequencydrive (VFD), a single shaft electric motor, and a single hydraulic pumpmounted on a single pump trailer to pump a fracking media into a well toexecute a fracking operation to extract a fluid from the well,comprising: generating electric power by a power generation system at apower generation voltage level; distributing by a power distributiontrailer the electric power at the power generation voltage levelgenerated by the power generation system and electric power at anauxiliary voltage level to a single VFD configuration on the single pumptrailer, wherein the electric power at the auxiliary voltage levelcontrols an operation of a plurality of auxiliary systems associatedwith the single pump trailer; converting by the single VFD configurationthe electric power at the power generation voltage level distributedfrom the power distribution trailer to a VFD voltage level and drive thesingle shaft electric motor to control the operation of the single shaftelectric motor and the single hydraulic pump, wherein the VFD voltagelevel is a voltage level that is required to drive the single shaftelectric motor; driving the single shaft electric motor that ispositioned on the single pump trailer with the single VFD at the VFDvoltage level to control the operation of the single shaft electricmotor and the single hydraulic pump; controlling operation of theplurality of auxiliary systems based on the electric power at theauxiliary voltage level; and segmenting, by a plurality of VFD cellswith each VFD cell isolated from each other, the electric power at thepower generation voltage level into a plurality of partitions, whereineach partition when reconnected into a configuration generates electricpower at the VFD voltage level to drive the single shaft electric motorwith a decrease in harmonics included in a VFD current waveform of theelectric power at the VFD voltage level.
 8. The method of claim 7,wherein the converting further comprises: applying by a VFD transformera phase shift to each of the partitions generated from the segmentationof the electric power at the power generation voltage level by each ofthe VFD cells isolated from each other VFD cell, wherein the phase shiftapplied to each partition when reconnected into the configurationgenerates electric power at the VFD voltage level to drive the singleshaft electric motor with the decrease in harmonics included in the VFDcurrent waveform of the electric power at the VFD voltage level.
 9. Themethod of claim 8, further comprising: receiving the electric power bythe VFD transformer at the power generation voltage level and theelectric power at the auxiliary voltage level as distributed by thepower generation trailer; and pre-charging a plurality of capacitorsassociated with each of the VFD cells to a voltage threshold with theelectric power at the auxiliary voltage level to prevent an in-rushcurrent that propagates to the power generation system after the VFDtransformer provides the electric power at the power generation voltagelevel to each of the VFD cells before the capacitors are pre-charged tothe voltage threshold, wherein the voltage threshold is a percentage ofthe power generation voltage level that the capacitors are to bepre-charged to prevent the in-rush current after the VFD transformerprovides the electric power at the power generation voltage level. 10.The method of claim 8, further comprising: monitoring by a VFDcontroller the capacitors associated with each of the VFD cells todetermine whether the pre-charge of each of the capacitors satisfies thevoltage threshold; maintaining the VFD relay in the open state when thepre-charge of each of the capacitors associated with each of the VFDcells is below the voltage threshold to prevent the electric power atthe power generation voltage level from propagating to each of the VFDcells; and transitioning the VFD relay from the open state to the closedstate when the pre-charge of each of the capacitors associated with eachof the VFD cells satisfies the voltage threshold to enable the electricpower at the power generation voltage level to propagate to each of theVFD cells.
 11. The method of claim 9, further comprising: preventing bya VFD relay the electric power at the power generation voltage levelfrom propagating to each of the VFD cells when the VFD relay is in anopen state; and allowing the electric power at the power generationvoltage level to propagate to each of the VFD cells when the VFD relayis in a closed state.
 12. The method of claim 10, further comprising:enabling, by at least one VFD contactor with each VFD contactorelectrically connected to two different VFD cells, the two different VFDcells that the at least one VFD contactor is electrically connected tocontinue to operate in generating the electric power at the VFD voltagelevel to drive the single shaft electric pump at a full capacity,wherein the single shaft electric motor is driven at a full capacitywhen each of the VFD cells included in the VFD configuration operates ingenerating the electric power at the VFD voltage level to drive thesingle shaft electric pump at the full capacity, bypassing at least oneof the two different VFD cells that the at least one VFD contactor iselectrically connected to prevent the at least one of the two differentVFD cells from generating the electric power at the VFD voltage level todrive the single shaft electric motor at the full capacity, wherein eachVFD cell included in the VFD configuration that is not bypassed the atleast one VFD contactor to continue to operate in generating theelectric power at a reduced VFD voltage level that is less than theelectric power at the VFD voltage level to drive the single shaftelectric pump at a reduced capacity that is less than the full capacity.13. An electric driven hydraulic fracking system that positions a singlevariable frequency drive (VFD), a single shaft electric motor, and asingle hydraulic pump mounted on a single pump trailer to pump afracking media into a fracking well to execute a fracking operation toextract a fluid from the fracking well, comprises: a power generationsystem that that is configured to generate electric power at a powergeneration voltage level; a power distribution trailer that isconfigured to distribute the electric power generated by the powergeneration system at the power generation voltage level and electricpower at an auxiliary voltage level to a plurality of VFD configurationspositioned on a plurality of single pump trailers, wherein the electricpower at the auxiliary voltage level controls an operation of aplurality auxiliary systems associated with each of the single pumptrailers; and a pump configuration that includes the each VFDconfiguration, each single shaft electric motor from a plurality ofsingle shaft electric motors, and a single shaft hydraulic pump from asingle shaft hydraulic pumps mounted on a corresponding single pumptrailer from the plurality of single pump trailers, wherein: each singleVFD configuration from the plurality of single VFD configurations isconfigured to: convert the electric power at the power generationvoltage level distributed from the power distribution trailer to a VFDvoltage level and drive each corresponding single shaft electric motorto control the operation of each corresponding single shaft electricmotor and each corresponding single hydraulic pump, wherein the VFDvoltage level is a voltage level that is required to drive each singleshaft electric motor, and control operation of the plurality ofauxiliary systems associated with each single pump trailer based on theelectric power at the auxiliary voltage level wherein: each single VFDconfiguration includes a plurality of VFD cells with each VFD cellisolated from each other VFD cell and configured to segment the electricpower at the power generation voltage level into a plurality ofpartitions, wherein each partition when reconnected into a configurationgenerates electric power at the VFD voltage level to drive eachcorresponding single shaft electric motor with a decrease in harmonicsincluded in a VFD current waveform of the electric power at the VFDvoltage level.
 14. The electric driven hydraulic fracking system ofclaim 13, wherein each VFD configuration further comprises: a VFDtransformer that is configured to apply a phase shift to each of thepartitions generated from the segmentation of the electric power at thepower generation voltage level by each of the VFD cells isolated fromeach other VFD cell, wherein the phase shift applied to each partitionwhen reconnected into the configuration generates electric power at theVFD voltage level to drive each corresponding single shaft electricmotor with a decrease in harmonics included in the VFD current waveformof the electric power at the VFD voltage level.
 15. The electric drivenhydraulic fracking system of claim 14, wherein each VFD transformerincluded in each VFD configuration is further configured to: receive theelectric power at the power generation voltage level and the electricpower at the auxiliary voltage level as distributed by the powergeneration trailer; and pre-charge a plurality of capacitors associatedwith each of the VFD cells included in each corresponding VFDconfiguration to a voltage threshold with the electric power at theauxiliary voltage level to prevent an in-rush current that propagates tothe power generation system after the corresponding VFD transformerprovides the electric power at the power generation voltage level toeach of the corresponding VFD cells before the capacitors arepre-charged to the voltage threshold, wherein the voltage threshold is apercentage of the power generation voltage level that the capacitors areto be pre-charged to prevent the in-rush current after the correspondingVFD transformer provides the electric power at the power generationvoltage level.
 16. The electric driven hydraulic fracking system ofclaim 15, wherein each VFD configuration further comprises: a VFD relaythat is configured to: prevent the electric power at the powergeneration voltage level from propagating to each of the VFD cellsincluded in each corresponding VFD configuration when the VFD relay isin an open state; and allow the electric power at the power generationvoltage level to propagate to each of the VFD cells included in eachcorresponding VFD configuration when the VFD relay is in a closed state.17. The electric driven hydraulic fracking system of claim 15, whereineach VFD configuration further comprises: a VFD controller that isconfigured to: monitor the capacitors associated with each of the VFDcells included in each corresponding VFD configuration to determinewhether the pre-charge of each of the capacitors satisfies the voltagethreshold, maintain each corresponding VFD relay in the open state whenthe pre-charge of each of the capacitors associated with each of the VFDcells included in each corresponding VFD configuration is below thevoltage threshold to prevent the electric power at the power generationvoltage level from propagating to each of the VFD cells included in eachcorresponding VFD configuration, and transition each corresponding VFDrelay from the open state to the closed state when the pre-charge ofeach of the capacitors associated with each of the VFD cells included ineach VFD configuration satisfies the voltage threshold to enable theelectric power at the power generation voltage level to propagate toeach of the VFD cells included in each VFD configuration.